diff --git a/src/Compilers/CSharp/Test/Symbol/Symbols/DefaultInterfaceImplementationTests.cs b/src/Compilers/CSharp/Test/Symbol/Symbols/DefaultInterfaceImplementationTests.cs
index 207cf2d2cab45858232fcd6361dea15e3e0b5c22..01c546fc5278f8e6baab5dd4ec7cfebbeea6b9e6 100644
--- a/src/Compilers/CSharp/Test/Symbol/Symbols/DefaultInterfaceImplementationTests.cs
+++ b/src/Compilers/CSharp/Test/Symbol/Symbols/DefaultInterfaceImplementationTests.cs
@@ -27972,6 +27972,8 @@ enum T4
     {
         B
     }
+
+    delegate void T5();
 }
 
 class Test1 : I1.T1
@@ -27983,6 +27985,7 @@ static void Main()
         System.Console.WriteLine(new I1.T2());
         System.Console.WriteLine(new I1.T3());
         System.Console.WriteLine(I1.T4.B);
+        System.Console.WriteLine(new I1.T5(a.M1));
     }
 
     public void M1()
@@ -28000,7 +28003,7 @@ private void ValidateNestedTypes_01(string source1, Accessibility expected = Acc
                                                  parseOptions: TestOptions.Regular,
                                                  targetFramework: targetFramework);
 
-            for (int i = 1; i <= 4; i++)
+            for (int i = 1; i <= 5; i++)
             {
                 Assert.Equal(expected, compilation1.GetMember("I1.T" + i).DeclaredAccessibility);
             }
@@ -28009,7 +28012,8 @@ private void ValidateNestedTypes_01(string source1, Accessibility expected = Acc
 @"M1
 I1+T2
 I1+T3
-B",
+B
+I1+T5",
                 verify: verify);
         }
 
@@ -28100,6 +28104,8 @@ public enum T4
     {
         B
     }
+
+    public delegate void T5();
 }
 
 class Test1 : I1.T1
@@ -28111,6 +28117,7 @@ static void Main()
         System.Console.WriteLine(new I1.T2());
         System.Console.WriteLine(new I1.T3());
         System.Console.WriteLine(I1.T4.B);
+        System.Console.WriteLine(new I1.T5(a.M1));
     }
 
     public void M1()
@@ -28144,6 +28151,8 @@ protected enum T4
     {
         B
     }
+
+    protected delegate void T5();
 }
 ";
             var source1 =
@@ -28157,6 +28166,7 @@ static void Main()
         System.Console.WriteLine(new I1.T2());
         System.Console.WriteLine(new I1.T3());
         System.Console.WriteLine(I1.T4.B);
+        System.Console.WriteLine(new I1.T5(a.M1));
     }
 
     class Test2 : I1.T1
@@ -28175,7 +28185,7 @@ public void M1()
                                                  parseOptions: TestOptions.Regular,
                                                  targetFramework: TargetFramework.DesktopLatestExtended);
 
-            for (int i = 1; i <= 4; i++)
+            for (int i = 1; i <= 5; i++)
             {
                 Assert.Equal(Accessibility.Protected, compilation1.GetMember("I1.T" + i).DeclaredAccessibility);
             }
@@ -28192,7 +28202,10 @@ public void M1()
                 Diagnostic(ErrorCode.ERR_RuntimeDoesNotSupportProtectedAccessForInterfaceMember, "T3").WithLocation(12, 22),
                 // (15,20): error CS8707: Target runtime doesn't support 'protected', 'protected internal', or 'private protected' accessibility for a member of an interface.
                 //     protected enum T4
-                Diagnostic(ErrorCode.ERR_RuntimeDoesNotSupportProtectedAccessForInterfaceMember, "T4").WithLocation(15, 20)
+                Diagnostic(ErrorCode.ERR_RuntimeDoesNotSupportProtectedAccessForInterfaceMember, "T4").WithLocation(15, 20),
+                // (20,29): error CS8707: Target runtime doesn't support 'protected', 'protected internal', or 'private protected' accessibility for a member of an interface.
+                //     protected delegate void T5();
+                Diagnostic(ErrorCode.ERR_RuntimeDoesNotSupportProtectedAccessForInterfaceMember, "T5").WithLocation(20, 29)
                 );
 
             var source2 =
@@ -28206,6 +28219,7 @@ static void Main()
         System.Console.WriteLine(new I1.T2());
         System.Console.WriteLine(new I1.T3());
         System.Console.WriteLine(I1.T4.B);
+        System.Console.WriteLine(new I1.T5(a.M1));
     }
 
     class Test2 : I1.T1
@@ -28238,9 +28252,15 @@ public void M1()
                 // (10,37): error CS0122: 'I1.T4' is inaccessible due to its protection level
                 //         System.Console.WriteLine(I1.T4.B);
                 Diagnostic(ErrorCode.ERR_BadAccess, "T4").WithArguments("I1.T4").WithLocation(10, 37),
-                // (13,22): error CS0122: 'I1.T1' is inaccessible due to its protection level
+                // (11,41): error CS0122: 'I1.T5' is inaccessible due to its protection level
+                //         System.Console.WriteLine(new I1.T5(a.M1));
+                Diagnostic(ErrorCode.ERR_BadAccess, "T5").WithArguments("I1.T5").WithLocation(11, 41),
+                // (11,46): error CS0122: 'I1.T1.M1()' is inaccessible due to its protection level
+                //         System.Console.WriteLine(new I1.T5(a.M1));
+                Diagnostic(ErrorCode.ERR_BadAccess, "M1").WithArguments("I1.T1.M1()").WithLocation(11, 46),
+                // (14,22): error CS0122: 'I1.T1' is inaccessible due to its protection level
                 //     class Test2 : I1.T1
-                Diagnostic(ErrorCode.ERR_BadAccess, "T1").WithArguments("I1.T1").WithLocation(13, 22)
+                Diagnostic(ErrorCode.ERR_BadAccess, "T1").WithArguments("I1.T1").WithLocation(14, 22)
                 };
 
             compilation2.VerifyDiagnostics(expected);
@@ -28263,7 +28283,8 @@ public void M1()
 @"M1
 I1+T2
 I1+T3
-B",
+B
+I1+T5",
                     verify: VerifyOnMonoOrCoreClr);
 
                 var compilation5 = CreateCompilation(source2, options: TestOptions.DebugExe,
@@ -28297,6 +28318,8 @@ protected internal enum T4
     {
         B
     }
+
+    protected internal delegate void T5();
 }
 ";
             var source1 =
@@ -28310,6 +28333,7 @@ static void Main()
         System.Console.WriteLine(new I1.T2());
         System.Console.WriteLine(new I1.T3());
         System.Console.WriteLine(I1.T4.B);
+        System.Console.WriteLine(new I1.T5(a.M1));
     }
 
     class Test2 : I1.T1
@@ -28333,6 +28357,7 @@ static void Main()
         System.Console.WriteLine(new I1.T2());
         System.Console.WriteLine(new I1.T3());
         System.Console.WriteLine(I1.T4.B);
+        System.Console.WriteLine(new I1.T5(a.M1));
     }
 
     class Test2 : I1.T1
@@ -28351,7 +28376,7 @@ public void M1()
                                                  parseOptions: TestOptions.Regular,
                                                  targetFramework: TargetFramework.DesktopLatestExtended);
 
-            for (int i = 1; i <= 4; i++)
+            for (int i = 1; i <= 5; i++)
             {
                 Assert.Equal(Accessibility.ProtectedOrInternal, compilation1.GetMember("I1.T" + i).DeclaredAccessibility);
             }
@@ -28368,7 +28393,10 @@ public void M1()
                 Diagnostic(ErrorCode.ERR_RuntimeDoesNotSupportProtectedAccessForInterfaceMember, "T3").WithLocation(12, 31),
                 // (15,29): error CS8707: Target runtime doesn't support 'protected', 'protected internal', or 'private protected' accessibility for a member of an interface.
                 //     protected internal enum T4
-                Diagnostic(ErrorCode.ERR_RuntimeDoesNotSupportProtectedAccessForInterfaceMember, "T4").WithLocation(15, 29)
+                Diagnostic(ErrorCode.ERR_RuntimeDoesNotSupportProtectedAccessForInterfaceMember, "T4").WithLocation(15, 29),
+                // (20,38): error CS8707: Target runtime doesn't support 'protected', 'protected internal', or 'private protected' accessibility for a member of an interface.
+                //     protected internal delegate void T5();
+                Diagnostic(ErrorCode.ERR_RuntimeDoesNotSupportProtectedAccessForInterfaceMember, "T5").WithLocation(20, 38)
                 );
 
 
@@ -28390,7 +28418,8 @@ public void M1()
 @"M1
 I1+T2
 I1+T3
-B",
+B
+I1+T5",
                     verify: VerifyOnMonoOrCoreClr);
 
                 var compilation5 = CreateCompilation(source2, options: TestOptions.DebugExe,
@@ -28414,9 +28443,15 @@ public void M1()
                     // (10,37): error CS0122: 'I1.T4' is inaccessible due to its protection level
                     //         System.Console.WriteLine(I1.T4.B);
                     Diagnostic(ErrorCode.ERR_BadAccess, "T4").WithArguments("I1.T4").WithLocation(10, 37),
-                    // (13,22): error CS0122: 'I1.T1' is inaccessible due to its protection level
+                    // (11,41): error CS0122: 'I1.T5' is inaccessible due to its protection level
+                    //         System.Console.WriteLine(new I1.T5(a.M1));
+                    Diagnostic(ErrorCode.ERR_BadAccess, "T5").WithArguments("I1.T5").WithLocation(11, 41),
+                    // (11,46): error CS0122: 'I1.T1.M1()' is inaccessible due to its protection level
+                    //         System.Console.WriteLine(new I1.T5(a.M1));
+                    Diagnostic(ErrorCode.ERR_BadAccess, "M1").WithArguments("I1.T1.M1()").WithLocation(11, 46),
+                    // (14,22): error CS0122: 'I1.T1' is inaccessible due to its protection level
                     //     class Test2 : I1.T1
-                    Diagnostic(ErrorCode.ERR_BadAccess, "T1").WithArguments("I1.T1").WithLocation(13, 22)
+                    Diagnostic(ErrorCode.ERR_BadAccess, "T1").WithArguments("I1.T1").WithLocation(14, 22)
                     );
             }
         }
@@ -28443,6 +28478,8 @@ internal enum T4
     {
         B
     }
+
+    internal delegate void T5();
 }
 ";
             var source2 =
@@ -28456,6 +28493,7 @@ static void Main()
         System.Console.WriteLine(new I1.T2());
         System.Console.WriteLine(new I1.T3());
         System.Console.WriteLine(I1.T4.B);
+        System.Console.WriteLine(new I1.T5(a.M1));
     }
 
     public void M1()
@@ -28489,7 +28527,13 @@ public void M1()
                 Diagnostic(ErrorCode.ERR_BadAccess, "T3").WithArguments("I1.T3").WithLocation(9, 41),
                 // (10,37): error CS0122: 'I1.T4' is inaccessible due to its protection level
                 //         System.Console.WriteLine(I1.T4.B);
-                Diagnostic(ErrorCode.ERR_BadAccess, "T4").WithArguments("I1.T4").WithLocation(10, 37)
+                Diagnostic(ErrorCode.ERR_BadAccess, "T4").WithArguments("I1.T4").WithLocation(10, 37),
+                // (11,41): error CS0122: 'I1.T5' is inaccessible due to its protection level
+                //         System.Console.WriteLine(new I1.T5(a.M1));
+                Diagnostic(ErrorCode.ERR_BadAccess, "T5").WithArguments("I1.T5").WithLocation(11, 41),
+                // (11,46): error CS0122: 'I1.T1.M1()' is inaccessible due to its protection level
+                //         System.Console.WriteLine(new I1.T5(a.M1));
+                Diagnostic(ErrorCode.ERR_BadAccess, "M1").WithArguments("I1.T1.M1()").WithLocation(11, 46)
                 };
             compilation2.VerifyDiagnostics(expected);
 
@@ -28521,6 +28565,8 @@ private enum T4
         B
     }
 
+    private delegate void T5();
+
     class Test1 : I1.T1
     {
         static void Main()
@@ -28530,6 +28576,7 @@ static void Main()
             System.Console.WriteLine(new I1.T2());
             System.Console.WriteLine(new I1.T3());
             System.Console.WriteLine(I1.T4.B);
+            System.Console.WriteLine(new I1.T5(a.M1));
         }
 
         public void M1()
@@ -28631,6 +28678,8 @@ private protected enum T4
     {
         B
     }
+
+    private protected delegate void T5();
 }
 ";
             var source1 =
@@ -28644,6 +28693,7 @@ static void Main()
         System.Console.WriteLine(new I1.T2());
         System.Console.WriteLine(new I1.T3());
         System.Console.WriteLine(I1.T4.B);
+        System.Console.WriteLine(new I1.T5(a.M1));
     }
 
     class Test2 : I1.T1
@@ -28667,6 +28717,7 @@ static void Main()
         System.Console.WriteLine(new I1.T2());
         System.Console.WriteLine(new I1.T3());
         System.Console.WriteLine(I1.T4.B);
+        System.Console.WriteLine(new I1.T5(a.M1));
     }
 
     class Test2 : I1.T1
@@ -28684,7 +28735,7 @@ public void M1()
                                                  parseOptions: TestOptions.Regular,
                                                  targetFramework: TargetFramework.DesktopLatestExtended);
 
-            for (int i = 1; i <= 4; i++)
+            for (int i = 1; i <= 5; i++)
             {
                 Assert.Equal(Accessibility.ProtectedAndInternal, compilation1.GetMember("I1.T" + i).DeclaredAccessibility);
             }
@@ -28701,7 +28752,10 @@ public void M1()
                 Diagnostic(ErrorCode.ERR_RuntimeDoesNotSupportProtectedAccessForInterfaceMember, "T3").WithLocation(12, 30),
                 // (15,28): error CS8707: Target runtime doesn't support 'protected', 'protected internal', or 'private protected' accessibility for a member of an interface.
                 //     private protected enum T4
-                Diagnostic(ErrorCode.ERR_RuntimeDoesNotSupportProtectedAccessForInterfaceMember, "T4").WithLocation(15, 28)
+                Diagnostic(ErrorCode.ERR_RuntimeDoesNotSupportProtectedAccessForInterfaceMember, "T4").WithLocation(15, 28),
+                // (20,37): error CS8707: Target runtime doesn't support 'protected', 'protected internal', or 'private protected' accessibility for a member of an interface.
+                //     private protected delegate void T5();
+                Diagnostic(ErrorCode.ERR_RuntimeDoesNotSupportProtectedAccessForInterfaceMember, "T5").WithLocation(20, 37)
                 );
 
             var compilation2 = CreateCompilation(source2 + source0, options: TestOptions.DebugExe,
@@ -28724,9 +28778,15 @@ public void M1()
                 // (10,37): error CS0122: 'I1.T4' is inaccessible due to its protection level
                 //         System.Console.WriteLine(I1.T4.B);
                 Diagnostic(ErrorCode.ERR_BadAccess, "T4").WithArguments("I1.T4").WithLocation(10, 37),
-                // (13,22): error CS0122: 'I1.T1' is inaccessible due to its protection level
+                // (11,41): error CS0122: 'I1.T5' is inaccessible due to its protection level
+                //         System.Console.WriteLine(new I1.T5(a.M1));
+                Diagnostic(ErrorCode.ERR_BadAccess, "T5").WithArguments("I1.T5").WithLocation(11, 41),
+                // (11,46): error CS0122: 'I1.T1.M1()' is inaccessible due to its protection level
+                //         System.Console.WriteLine(new I1.T5(a.M1));
+                Diagnostic(ErrorCode.ERR_BadAccess, "M1").WithArguments("I1.T1.M1()").WithLocation(11, 46),
+                // (14,22): error CS0122: 'I1.T1' is inaccessible due to its protection level
                 //     class Test2 : I1.T1
-                Diagnostic(ErrorCode.ERR_BadAccess, "T1").WithArguments("I1.T1").WithLocation(13, 22)
+                Diagnostic(ErrorCode.ERR_BadAccess, "T1").WithArguments("I1.T1").WithLocation(14, 22)
                 };
 
             compilation2.VerifyDiagnostics(expected);
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/AbstractKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/AbstractKeywordRecommenderTests.cs
index 31fc5a0831cf99940c5797ad48e36e6953968612..100dd63480f773f0f95322adb654610d4394d044 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/AbstractKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/AbstractKeywordRecommenderTests.cs
@@ -178,9 +178,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/AsyncKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/AsyncKeywordRecommenderTests.cs
index 6ab71ab0e2c23a1f7651c34e48f70d3337112546..8da196be4ffd0520c55c3aeaeeba91933257fd91 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/AsyncKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/AsyncKeywordRecommenderTests.cs
@@ -36,6 +36,15 @@ public async Task TestMethodDeclaration3()
 }");
         }
 
+        [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
+        public async Task TestInsideInterface()
+        {
+            await VerifyKeywordAsync(@"interface C
+{
+    $$
+}");
+        }
+
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
         public async Task TestMethodDeclarationInGlobalStatement1()
         {
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/ClassKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/ClassKeywordRecommenderTests.cs
index c315f005730dfecb6cd346d9afa806471103982b..c4ec710a884dac1863a8f75e0de8f9c39abf9158 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/ClassKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/ClassKeywordRecommenderTests.cs
@@ -178,9 +178,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/ConstKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/ConstKeywordRecommenderTests.cs
index a6385a1d78b67f0a263104ea5bb3c75bc37b455c..79934a9ab397963ec530a333d18adb5f53be77da 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/ConstKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/ConstKeywordRecommenderTests.cs
@@ -191,9 +191,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/DelegateKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/DelegateKeywordRecommenderTests.cs
index 161bfbb7c9026c4d73ed95644202e9f777ea99f3..9fdc3df67e69ae5c8d2c4d9019ace6c8573fc503 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/DelegateKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/DelegateKeywordRecommenderTests.cs
@@ -178,9 +178,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/EnumKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/EnumKeywordRecommenderTests.cs
index 96e537f8a9f5e0d0a8f2a63072cd625e2b1acd10..f118b91b3cd3420ac8c5ecea35a53ad063eb0a99 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/EnumKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/EnumKeywordRecommenderTests.cs
@@ -185,9 +185,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/ExternKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/ExternKeywordRecommenderTests.cs
index 9683dbb07995a1a4a1a18b9d85ab53acc5e7786d..83362626bf193bf41021da3679ffca59616b5411 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/ExternKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/ExternKeywordRecommenderTests.cs
@@ -167,9 +167,9 @@ public async Task TestInStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInInterface()
+        public async Task TestInInterface()
         {
-            await VerifyAbsenceAsync(
+            await VerifyKeywordAsync(
 @"interface I {
     $$");
         }
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/InterfaceKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/InterfaceKeywordRecommenderTests.cs
index 752506829fca89962006b0943178a571764090a0..3cd679878b3f0320aa2c647fd585f4dfef7c73eb 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/InterfaceKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/InterfaceKeywordRecommenderTests.cs
@@ -178,9 +178,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/InternalKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/InternalKeywordRecommenderTests.cs
index abacfc365610ceb10c25d7d47126d6edc0c88465..c089ef7b1c9126176fa4f7029fe9926b9c8c9c0c 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/InternalKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/InternalKeywordRecommenderTests.cs
@@ -178,9 +178,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/PartialKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/PartialKeywordRecommenderTests.cs
index 6ddbcaa6161310c8ff24ae3e91d05285a9a21607..c9152b8fa639fc4f3173c2bee16390739fde6b83 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/PartialKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/PartialKeywordRecommenderTests.cs
@@ -196,9 +196,9 @@ public async Task TestInsidePartialStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/PrivateKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/PrivateKeywordRecommenderTests.cs
index c06f9728d12b63d199e15521f10f5903c6929431..b5e404c3e51040e9271b69b4edb7a480e7465997 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/PrivateKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/PrivateKeywordRecommenderTests.cs
@@ -189,9 +189,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/ProtectedKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/ProtectedKeywordRecommenderTests.cs
index 85beb332798450d9e74b4cf2587ef42250cfba26..5e3442722318d5605b71ea229bef89dea025df82 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/ProtectedKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/ProtectedKeywordRecommenderTests.cs
@@ -160,9 +160,9 @@ public async Task TestNotInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/PublicKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/PublicKeywordRecommenderTests.cs
index badebb101fe7c359add6d0579c9a9bf3c2fc0b9f..4b2a40e49ab2b5610afab2c2c4f27b603a930554 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/PublicKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/PublicKeywordRecommenderTests.cs
@@ -181,7 +181,7 @@ public async Task TestInsideStruct()
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
         public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(
+            await VerifyKeywordAsync(
 @"interface I {
    $$");
         }
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/ReadOnlyKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/ReadOnlyKeywordRecommenderTests.cs
index a0f694315f44e8c19af7c0c5329aa9c11bebaa46..e752018d3588f86ede987b5b6e5cc8c46739ada7 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/ReadOnlyKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/ReadOnlyKeywordRecommenderTests.cs
@@ -191,9 +191,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/SealedKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/SealedKeywordRecommenderTests.cs
index 804dc01499ff4b691f060643933489a6cd350b6a..12f798daa07878fee0102021d91f474f4778123b 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/SealedKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/SealedKeywordRecommenderTests.cs
@@ -178,9 +178,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/StaticKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/StaticKeywordRecommenderTests.cs
index 44081357324aacdef1e421276ffc418b262002bb..09db0bb58ffd209a1bae430d5741cf22e617eb0b 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/StaticKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/StaticKeywordRecommenderTests.cs
@@ -180,9 +180,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/StructKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/StructKeywordRecommenderTests.cs
index 6bc55158a93c2c174333a9f96ebb2564cc515a51..d70acb638ff3ded671af86eb2fd6bf215a710c6c 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/StructKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/StructKeywordRecommenderTests.cs
@@ -234,9 +234,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/TypeKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/TypeKeywordRecommenderTests.cs
index dbe7806aa440d2b429a6125f3c93b37c94974490..be78194b3d4a394f3fea2b909111f9fd9d0e2c07 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/TypeKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/TypeKeywordRecommenderTests.cs
@@ -163,9 +163,9 @@ public async Task TestNotInMethodTypeParameters()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInInterface()
+        public async Task TestInInterface()
         {
-            await VerifyAbsenceAsync(
+            await VerifyKeywordAsync(
 @"interface I {
     [$$");
         }
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/VirtualKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/VirtualKeywordRecommenderTests.cs
index 6a6c80da720c4577b629440221012de08e107565..094d43b9d8d25cce24449c3a753fed5b70d73a5d 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/VirtualKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/VirtualKeywordRecommenderTests.cs
@@ -160,9 +160,9 @@ public async Task TestNotInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/EditorFeatures/CSharpTest2/Recommendations/VolatileKeywordRecommenderTests.cs b/src/EditorFeatures/CSharpTest2/Recommendations/VolatileKeywordRecommenderTests.cs
index f25ba8a5dd353a7c2416288cf8e91e2c6653dcf0..cb3e71d15d40bf4c959856d679ec55a25890109c 100644
--- a/src/EditorFeatures/CSharpTest2/Recommendations/VolatileKeywordRecommenderTests.cs
+++ b/src/EditorFeatures/CSharpTest2/Recommendations/VolatileKeywordRecommenderTests.cs
@@ -191,9 +191,9 @@ public async Task TestInsideStruct()
         }
 
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
-        public async Task TestNotInsideInterface()
+        public async Task TestInsideInterface()
         {
-            await VerifyAbsenceAsync(@"interface I {
+            await VerifyKeywordAsync(@"interface I {
    $$");
         }
 
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/AbstractKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/AbstractKeywordRecommender.cs
index e25266d01862b30a4821021a79058625b09e42ae..95e68a8301db2b4689c82369a6fcb0bbf870c6ef 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/AbstractKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/AbstractKeywordRecommender.cs
@@ -41,12 +41,12 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
                 context.IsGlobalStatementContext ||
                 context.IsMemberDeclarationContext(
                     validModifiers: s_validMemberModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassOnlyTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceTypeDeclarations,
                     canBePartial: false,
                     cancellationToken: cancellationToken) ||
                 context.IsTypeDeclarationContext(
                     validModifiers: s_validTypeModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: false,
                     cancellationToken: cancellationToken);
         }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/AsyncKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/AsyncKeywordRecommender.cs
index 07631942b44880de003f58b40f8a9d60b359e38b..6361425eac275e6723a4dbe2f9e049e53d3d200c 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/AsyncKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/AsyncKeywordRecommender.cs
@@ -36,7 +36,7 @@ private static bool InMemberDeclarationContext(int position, CSharpSyntaxContext
                 || context.SyntaxTree.IsGlobalMemberDeclarationContext(position, SyntaxKindSet.AllGlobalMemberModifiers, cancellationToken)
                 || context.IsMemberDeclarationContext(
                     validModifiers: SyntaxKindSet.AllMemberModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: true,
                     cancellationToken: cancellationToken);
         }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ClassKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ClassKeywordRecommender.cs
index c88df979b2a7c9c2e37a29e8015d26b4486459c2..07a73219b6dbf243b8530c1f3c4923a16ba08960 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ClassKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ClassKeywordRecommender.cs
@@ -34,7 +34,7 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
                 context.IsGlobalStatementContext ||
                 context.IsTypeDeclarationContext(
                     validModifiers: s_validModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: true,
                     cancellationToken: cancellationToken) ||
                 syntaxTree.IsTypeParameterConstraintStartContext(position, context.LeftToken, cancellationToken);
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ConstKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ConstKeywordRecommender.cs
index eb27a093dbd72397cca3e7e1d1f9ffd7f2489679..25109fc200192fd03f5e5913553f6d2721b8d8c2 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ConstKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ConstKeywordRecommender.cs
@@ -44,7 +44,7 @@ private bool IsMemberDeclarationContext(CSharpSyntaxContext context, Cancellatio
                 context.SyntaxTree.IsGlobalMemberDeclarationContext(context.Position, s_validGlobalModifiers, cancellationToken) ||
                 context.IsMemberDeclarationContext(
                     validModifiers: s_validModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: false,
                     cancellationToken: cancellationToken);
         }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/DelegateKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/DelegateKeywordRecommender.cs
index f0e7ffe0b4548acddc8ead569473f0acf27cd942..dadb292b01e3e466f08a3e0ae8c33d018b24448a 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/DelegateKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/DelegateKeywordRecommender.cs
@@ -32,7 +32,7 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
                 IsAfterAsyncKeywordInExpressionContext(context, cancellationToken) ||
                 context.IsTypeDeclarationContext(
                     validModifiers: s_validModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: false,
                     cancellationToken: cancellationToken);
         }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/EnumKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/EnumKeywordRecommender.cs
index 7ec27bbf380d5b41eb6d7df0926f70528fc67d95..0349a238dbf2b69fcb8f4ef3c3be76c475c7d2cd 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/EnumKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/EnumKeywordRecommender.cs
@@ -28,7 +28,7 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
                 context.IsGlobalStatementContext ||
                 context.IsTypeDeclarationContext(
                     validModifiers: s_validModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: false,
                     cancellationToken: cancellationToken);
         }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ExternKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ExternKeywordRecommender.cs
index c246c1287285d2f30d4becaa5d8659c5daa819dd..e5663b526806640b0db911aa89521e883a9f0ab7 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ExternKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ExternKeywordRecommender.cs
@@ -47,7 +47,7 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
                 syntaxTree.IsGlobalMemberDeclarationContext(position, s_validGlobalModifiers, cancellationToken) ||
                 context.IsMemberDeclarationContext(
                     validModifiers: s_validModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: false,
                     cancellationToken: cancellationToken);
         }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/InterfaceKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/InterfaceKeywordRecommender.cs
index a4490a32f0d8698c51c101d6032fb12255c0e5ea..abc51dd8c9ad5aaf07476e61e254f305edcae120 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/InterfaceKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/InterfaceKeywordRecommender.cs
@@ -29,7 +29,7 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
                 context.IsGlobalStatementContext ||
                 context.IsTypeDeclarationContext(
                     validModifiers: s_validModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: true,
                     cancellationToken: cancellationToken);
         }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/InternalKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/InternalKeywordRecommender.cs
index e3a697e34e59d674b45169aa4b42da84dd25a81e..90b14e3b636bc3bc4306d21caee0d8248acdfbc4 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/InternalKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/InternalKeywordRecommender.cs
@@ -37,7 +37,7 @@ private static bool IsValidContextForAccessor(CSharpSyntaxContext context)
         private static bool IsValidContextForMember(CSharpSyntaxContext context, CancellationToken cancellationToken)
         {
             if (context.SyntaxTree.IsGlobalMemberDeclarationContext(context.Position, SyntaxKindSet.AllGlobalMemberModifiers, cancellationToken) ||
-                context.IsMemberDeclarationContext(validModifiers: SyntaxKindSet.AllMemberModifiers, validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
+                context.IsMemberDeclarationContext(validModifiers: SyntaxKindSet.AllMemberModifiers, validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
             {
                 return CheckPreviousAccessibilityModifiers(context);
             }
@@ -47,7 +47,7 @@ private static bool IsValidContextForMember(CSharpSyntaxContext context, Cancell
 
         private static bool IsValidContextForType(CSharpSyntaxContext context, CancellationToken cancellationToken)
         {
-            if (context.IsTypeDeclarationContext(validModifiers: SyntaxKindSet.AllTypeModifiers, validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
+            if (context.IsTypeDeclarationContext(validModifiers: SyntaxKindSet.AllTypeModifiers, validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
             {
                 return CheckPreviousAccessibilityModifiers(context);
             }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/PartialKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/PartialKeywordRecommender.cs
index 2baa1043965134bdeb45ad12bc682f0dc1018f45..ca8d3652b3b77ac5083a6e8449408fd596cae894 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/PartialKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/PartialKeywordRecommender.cs
@@ -34,7 +34,7 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
 
         private bool IsMemberDeclarationContext(CSharpSyntaxContext context, CancellationToken cancellationToken)
         {
-            if (context.IsMemberDeclarationContext(validModifiers: s_validMemberModifiers, validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
+            if (context.IsMemberDeclarationContext(validModifiers: s_validMemberModifiers, validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
             {
                 var token = context.LeftToken;
                 var decl = token.GetAncestor<TypeDeclarationSyntax>();
@@ -55,7 +55,7 @@ private bool IsTypeDeclarationContext(CSharpSyntaxContext context, CancellationT
         {
             return context.IsTypeDeclarationContext(
                 validModifiers: SyntaxKindSet.AllTypeModifiers,
-                validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                 canBePartial: false,
                 cancellationToken: cancellationToken);
         }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/PrivateKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/PrivateKeywordRecommender.cs
index 55b9238ed72aceb18ed36d7ef0a2ca77c65984e6..01cd3dec5da2d8b358a9b733d8d14d5947a73782 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/PrivateKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/PrivateKeywordRecommender.cs
@@ -37,7 +37,7 @@ private static bool IsValidContextForAccessor(CSharpSyntaxContext context)
         private static bool IsValidContextForMember(CSharpSyntaxContext context, CancellationToken cancellationToken)
         {
             if (context.SyntaxTree.IsGlobalMemberDeclarationContext(context.Position, SyntaxKindSet.AllGlobalMemberModifiers, cancellationToken) ||
-                context.IsMemberDeclarationContext(validModifiers: SyntaxKindSet.AllMemberModifiers, validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
+                context.IsMemberDeclarationContext(validModifiers: SyntaxKindSet.AllMemberModifiers, validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
             {
                 var modifiers = context.PrecedingModifiers;
 
@@ -58,7 +58,7 @@ private static bool IsValidContextForMember(CSharpSyntaxContext context, Cancell
 
         private static bool IsValidContextForType(CSharpSyntaxContext context, CancellationToken cancellationToken)
         {
-            if (context.IsTypeDeclarationContext(validModifiers: SyntaxKindSet.AllTypeModifiers, validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
+            if (context.IsTypeDeclarationContext(validModifiers: SyntaxKindSet.AllTypeModifiers, validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
             {
                 // private things can't be in namespaces.
                 var typeDecl = context.ContainingTypeDeclaration;
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ProtectedKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ProtectedKeywordRecommender.cs
index b94e048dfe0fc7483aab879659bb4e95cabe7988..4ca721c67880f9becaeb7b5c3784148da73d067c 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ProtectedKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ProtectedKeywordRecommender.cs
@@ -35,7 +35,7 @@ private static bool IsValidContextForAccessor(CSharpSyntaxContext context)
 
         private static bool IsValidContextForMember(CSharpSyntaxContext context, CancellationToken cancellationToken)
         {
-            if (context.IsMemberDeclarationContext(validModifiers: SyntaxKindSet.AllMemberModifiers, validTypeDeclarations: SyntaxKindSet.ClassOnlyTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
+            if (context.IsMemberDeclarationContext(validModifiers: SyntaxKindSet.AllMemberModifiers, validTypeDeclarations: SyntaxKindSet.ClassInterfaceTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
             {
                 return CheckPreviousAccessibilityModifiers(context);
             }
@@ -45,7 +45,7 @@ private static bool IsValidContextForMember(CSharpSyntaxContext context, Cancell
 
         private static bool IsValidContextForType(CSharpSyntaxContext context, CancellationToken cancellationToken)
         {
-            if (context.IsTypeDeclarationContext(validModifiers: SyntaxKindSet.AllTypeModifiers, validTypeDeclarations: SyntaxKindSet.ClassOnlyTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
+            if (context.IsTypeDeclarationContext(validModifiers: SyntaxKindSet.AllTypeModifiers, validTypeDeclarations: SyntaxKindSet.ClassInterfaceTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
             {
                 // protected things can't be in namespaces.
                 var typeDecl = context.ContainingTypeDeclaration;
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/PublicKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/PublicKeywordRecommender.cs
index fca4417dbb96c10571c0a225a0d9e1449a32f601..90255bd11027d0bf1dd3867c8fca962a399b538b 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/PublicKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/PublicKeywordRecommender.cs
@@ -26,7 +26,7 @@ private static bool IsValidContextForMember(CSharpSyntaxContext context, Cancell
             if (context.SyntaxTree.IsGlobalMemberDeclarationContext(context.Position, SyntaxKindSet.AllGlobalMemberModifiers, cancellationToken) ||
                 context.IsMemberDeclarationContext(
                     validModifiers: SyntaxKindSet.AllMemberModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: false,
                     cancellationToken: cancellationToken))
             {
@@ -38,7 +38,7 @@ private static bool IsValidContextForMember(CSharpSyntaxContext context, Cancell
 
         private static bool IsValidContextForType(CSharpSyntaxContext context, CancellationToken cancellationToken)
         {
-            if (context.IsTypeDeclarationContext(validModifiers: SyntaxKindSet.AllTypeModifiers, validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
+            if (context.IsTypeDeclarationContext(validModifiers: SyntaxKindSet.AllTypeModifiers, validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
             {
                 return CheckPreviousAccessibilityModifiers(context);
             }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ReadOnlyKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ReadOnlyKeywordRecommender.cs
index 53d5ce247bb71e99005e9862dc0f2b990d38d0ae..a8b86a243a68b06d5dc8f43f53a70b158418918c 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ReadOnlyKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/ReadOnlyKeywordRecommender.cs
@@ -34,7 +34,7 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
                 context.SyntaxTree.IsGlobalMemberDeclarationContext(context.Position, SyntaxKindSet.AllGlobalMemberModifiers, cancellationToken) ||
                 context.IsMemberDeclarationContext(
                     validModifiers: s_validMemberModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: false,
                     cancellationToken: cancellationToken);
         }
@@ -46,7 +46,7 @@ private static bool IsRefReadOnlyContext(CSharpSyntaxContext context)
         private static bool IsValidContextForType(CSharpSyntaxContext context, CancellationToken cancellationToken)
         {
             return context.IsTypeDeclarationContext(validModifiers: SyntaxKindSet.AllTypeModifiers,
-                validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations, canBePartial: true, cancellationToken);
+                validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations, canBePartial: true, cancellationToken);
         }
     }
 }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/RefKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/RefKeywordRecommender.cs
index fdb6517b2bcc791a36d1fd4d216442a41e14c19a..0a82c079529837b1f4b031dc78ca159be7090809 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/RefKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/RefKeywordRecommender.cs
@@ -167,7 +167,7 @@ private static bool IsValidRefExpressionContext(SyntaxTree syntaxTree, int posit
         private static bool IsValidContextForType(CSharpSyntaxContext context, CancellationToken cancellationToken)
         {
             return context.IsTypeDeclarationContext(validModifiers: SyntaxKindSet.AllTypeModifiers,
-                validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations, canBePartial: true, cancellationToken);
+                validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations, canBePartial: true, cancellationToken);
         }
     }
 }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/SealedKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/SealedKeywordRecommender.cs
index 31560c433d35707ee0d0929dce0593c7a3aef0fc..44118cd5a6fa8acfc038c344a31901c9f8fedd8b 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/SealedKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/SealedKeywordRecommender.cs
@@ -41,12 +41,12 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
                 context.IsGlobalStatementContext ||
                 context.IsMemberDeclarationContext(
                     validModifiers: s_validMemberModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassOnlyTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceTypeDeclarations,
                     canBePartial: false,
                     cancellationToken: cancellationToken) ||
                 context.IsTypeDeclarationContext(
                     validModifiers: s_validTypeModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: false,
                     cancellationToken: cancellationToken);
         }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/StaticKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/StaticKeywordRecommender.cs
index 6ca82c848a5237fd920b51eacdd5649cf418c087..40c5da210c0edb8e55a3a60c1b37ee15a0196337 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/StaticKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/StaticKeywordRecommender.cs
@@ -66,7 +66,7 @@ private static bool IsValidContextForMember(CSharpSyntaxContext context, Cancell
                 context.SyntaxTree.IsGlobalMemberDeclarationContext(context.Position, s_validGlobalMemberModifiers, cancellationToken) ||
                 context.IsMemberDeclarationContext(
                     validModifiers: s_validMemberModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: false,
                     cancellationToken: cancellationToken);
         }
@@ -75,7 +75,7 @@ private static bool IsValidContextForType(CSharpSyntaxContext context, Cancellat
         {
             return context.IsTypeDeclarationContext(
                 validModifiers: s_validTypeModifiers,
-                validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                 canBePartial: false,
                 cancellationToken: cancellationToken);
         }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/StructKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/StructKeywordRecommender.cs
index 7cc8ce7305975b9d1a2f7ee4386b493a4fd4d766..9f004eefdbcb8aa318965640c5b760210e911c84 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/StructKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/StructKeywordRecommender.cs
@@ -32,7 +32,7 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
                 context.IsGlobalStatementContext ||
                 context.IsTypeDeclarationContext(
                     validModifiers: s_validModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: true,
                     cancellationToken: cancellationToken) ||
                 syntaxTree.IsTypeParameterConstraintStartContext(position, context.LeftToken, cancellationToken);
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/UnsafeKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/UnsafeKeywordRecommender.cs
index b72400ea6df0e40f1eebde7fff8658596a46d35e..0f3506085e597f4b70f211fb6cc30a407a03365b 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/UnsafeKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/UnsafeKeywordRecommender.cs
@@ -61,7 +61,7 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
             return
                 context.IsStatementContext ||
                 context.IsGlobalStatementContext ||
-                context.IsTypeDeclarationContext(validModifiers: s_validTypeModifiers, validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken) ||
+                context.IsTypeDeclarationContext(validModifiers: s_validTypeModifiers, validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken) ||
                 syntaxTree.IsGlobalMemberDeclarationContext(position, s_validGlobalMemberModifiers, cancellationToken) ||
                 context.IsMemberDeclarationContext(
                     validModifiers: s_validMemberModifiers,
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/VirtualKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/VirtualKeywordRecommender.cs
index d6dde435d1b8bb53e2fb0dc3dfd8f18519dfa4b1..b4ac8650288b711da28d1a3b69e984277afeebdc 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/VirtualKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/VirtualKeywordRecommender.cs
@@ -28,7 +28,7 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
         {
             return context.IsMemberDeclarationContext(
                 validModifiers: s_validMemberModifiers,
-                validTypeDeclarations: SyntaxKindSet.ClassOnlyTypeDeclarations,
+                validTypeDeclarations: SyntaxKindSet.ClassInterfaceTypeDeclarations,
                 canBePartial: false,
                 cancellationToken: cancellationToken);
         }
diff --git a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/VolatileKeywordRecommender.cs b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/VolatileKeywordRecommender.cs
index 58463e3b474bada0be1c20e43922ea209a24221e..bedad47f92b8e7360e65d5953bbae1b63484a7fe 100644
--- a/src/Features/CSharp/Portable/Completion/KeywordRecommenders/VolatileKeywordRecommender.cs
+++ b/src/Features/CSharp/Portable/Completion/KeywordRecommenders/VolatileKeywordRecommender.cs
@@ -31,7 +31,7 @@ protected override bool IsValidContext(int position, CSharpSyntaxContext context
                 context.SyntaxTree.IsGlobalMemberDeclarationContext(context.Position, SyntaxKindSet.AllGlobalMemberModifiers, cancellationToken) ||
                 context.IsMemberDeclarationContext(
                     validModifiers: s_validMemberModifiers,
-                    validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations,
+                    validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations,
                     canBePartial: false,
                     cancellationToken: cancellationToken);
         }
diff --git a/src/Workspaces/CSharp/Portable/Extensions/ContextQuery/CSharpSyntaxContext.cs b/src/Workspaces/CSharp/Portable/Extensions/ContextQuery/CSharpSyntaxContext.cs
index 7d301e922173bd940331908274cacb2315876ae9..924b769f80f0f7566ac2db53fffcca5f7d1ce561 100644
--- a/src/Workspaces/CSharp/Portable/Extensions/ContextQuery/CSharpSyntaxContext.cs
+++ b/src/Workspaces/CSharp/Portable/Extensions/ContextQuery/CSharpSyntaxContext.cs
@@ -275,7 +275,7 @@ public bool IsTypeAttributeContext(CancellationToken cancellationToken)
             if (token.Kind() == SyntaxKind.OpenBracketToken &&
                 token.Parent.Kind() == SyntaxKind.AttributeList &&
                 this.SyntaxTree.IsTypeDeclarationContext(
-                    token.SpanStart, contextOpt: null, validModifiers: null, validTypeDeclarations: SyntaxKindSet.ClassStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
+                    token.SpanStart, contextOpt: null, validModifiers: null, validTypeDeclarations: SyntaxKindSet.ClassInterfaceStructTypeDeclarations, canBePartial: false, cancellationToken: cancellationToken))
             {
                 return true;
             }
diff --git a/src/Workspaces/CSharp/Portable/Extensions/ContextQuery/SyntaxTreeExtensions.cs b/src/Workspaces/CSharp/Portable/Extensions/ContextQuery/SyntaxTreeExtensions.cs
index 2e62455fb7841cf2da0363dba69e17aac01d31c9..d916631e43afd706780f12911c541b99cd63e5dc 100644
--- a/src/Workspaces/CSharp/Portable/Extensions/ContextQuery/SyntaxTreeExtensions.cs
+++ b/src/Workspaces/CSharp/Portable/Extensions/ContextQuery/SyntaxTreeExtensions.cs
@@ -407,7 +407,7 @@ public static bool IsAttributeNameContext(this SyntaxTree syntaxTree, int positi
 
             if (token.IsKind(SyntaxKind.OpenBraceToken))
             {
-                if (token.Parent.IsKind(SyntaxKind.ClassDeclaration, SyntaxKind.StructDeclaration))
+                if (token.Parent.IsKind(SyntaxKind.ClassDeclaration, SyntaxKind.StructDeclaration, SyntaxKind.InterfaceDeclaration))
                 {
                     return true;
                 }
@@ -511,8 +511,8 @@ public static bool IsAttributeNameContext(this SyntaxTree syntaxTree, int positi
             bool canBePartial,
             CancellationToken cancellationToken)
         {
-            // We only allow nested types inside a class or struct, not inside a
-            // an interface or enum.
+            // We only allow nested types inside a class, struct, or interface, not inside a
+            // an enum.
             var typeDecl = contextOpt != null
                 ? contextOpt.ContainingTypeDeclaration
                 : syntaxTree.GetContainingTypeDeclaration(position, cancellationToken);
diff --git a/src/Workspaces/CSharp/Portable/Utilities/SyntaxKindSet.cs b/src/Workspaces/CSharp/Portable/Utilities/SyntaxKindSet.cs
index 133ff2d9ecb0776efc3574cd01bf1b88af796c31..3984b2e2339633c73f7759d5b51624c01a045687 100644
--- a/src/Workspaces/CSharp/Portable/Utilities/SyntaxKindSet.cs
+++ b/src/Workspaces/CSharp/Portable/Utilities/SyntaxKindSet.cs
@@ -75,15 +75,16 @@ internal class SyntaxKindSet
             SyntaxKind.StructDeclaration,
         };
 
-        public static readonly ISet<SyntaxKind> ClassStructTypeDeclarations = new HashSet<SyntaxKind>(SyntaxFacts.EqualityComparer)
+        public static readonly ISet<SyntaxKind> ClassInterfaceTypeDeclarations = new HashSet<SyntaxKind>(SyntaxFacts.EqualityComparer)
         {
+            SyntaxKind.InterfaceDeclaration,
             SyntaxKind.ClassDeclaration,
-            SyntaxKind.StructDeclaration,
         };
 
-        public static readonly ISet<SyntaxKind> ClassOnlyTypeDeclarations = new HashSet<SyntaxKind>(SyntaxFacts.EqualityComparer)
+        public static readonly ISet<SyntaxKind> ClassStructTypeDeclarations = new HashSet<SyntaxKind>(SyntaxFacts.EqualityComparer)
         {
             SyntaxKind.ClassDeclaration,
+            SyntaxKind.StructDeclaration,
         };
 
         public static readonly ISet<SyntaxKind> StructOnlyTypeDeclarations = new HashSet<SyntaxKind>(SyntaxFacts.EqualityComparer)