Update unit1.json

qis/unit1.json

 {
     "code":200,
     "unit":{
-        "ting":"topic1",
-        "ting":"topic2",
-        "ting":"topic3",
-        "ting":"review of unit1"
+        "1":"topic1",
+        "2":"topic2",
+        "3":"topic3",
+        "4":"review of unit1"
     }, 
     "txt":{
         "topic1":{