diff --git a/develop/doc/_sources/design/csp.md.txt b/develop/doc/_sources/design/csp.md.txt
index ae2e3e1b998f949b5ca34707fa598725ef9fcbfd..10d936860fab7e09241e968a63526c7d86d3e568 100644
--- a/develop/doc/_sources/design/csp.md.txt
+++ b/develop/doc/_sources/design/csp.md.txt
@@ -144,8 +144,9 @@ ch = fluid.make_channel(dtype=INT, buffer_size)
 # Now write three elements to the channel
 with fluid.while(steps=buffer_size):
   fluid.send(ch, step)
-  fluid.close_channel(ch)
-  
+
+fluid.close_channel(ch)
+
 with fluid.while(steps=buffer_size):
   fluid.print(fluid.recv(ch))
 ```
diff --git a/develop/doc/design/csp.html b/develop/doc/design/csp.html
index 01d5cf2f5ef979ba71494751d067b3cf7fb94da7..a420daca457b5355e87acd58392524327517a604 100644
--- a/develop/doc/design/csp.html
+++ b/develop/doc/design/csp.html
@@ -325,8 +325,9 @@
 <span class="c1"># Now write three elements to the channel</span>
 <span class="k">with</span> <span class="n">fluid</span><span class="o">.</span><span class="k">while</span><span class="p">(</span><span class="n">steps</span><span class="o">=</span><span class="n">buffer_size</span><span class="p">):</span>
   <span class="n">fluid</span><span class="o">.</span><span class="n">send</span><span class="p">(</span><span class="n">ch</span><span class="p">,</span> <span class="n">step</span><span class="p">)</span>
-  <span class="n">fluid</span><span class="o">.</span><span class="n">close_channel</span><span class="p">(</span><span class="n">ch</span><span class="p">)</span>
-  
+
+<span class="n">fluid</span><span class="o">.</span><span class="n">close_channel</span><span class="p">(</span><span class="n">ch</span><span class="p">)</span>
+
 <span class="k">with</span> <span class="n">fluid</span><span class="o">.</span><span class="k">while</span><span class="p">(</span><span class="n">steps</span><span class="o">=</span><span class="n">buffer_size</span><span class="p">):</span>
   <span class="n">fluid</span><span class="o">.</span><span class="k">print</span><span class="p">(</span><span class="n">fluid</span><span class="o">.</span><span class="n">recv</span><span class="p">(</span><span class="n">ch</span><span class="p">))</span>
 </pre></div>
diff --git a/develop/doc_cn/_sources/design/csp.md.txt b/develop/doc_cn/_sources/design/csp.md.txt
index ae2e3e1b998f949b5ca34707fa598725ef9fcbfd..10d936860fab7e09241e968a63526c7d86d3e568 100644
--- a/develop/doc_cn/_sources/design/csp.md.txt
+++ b/develop/doc_cn/_sources/design/csp.md.txt
@@ -144,8 +144,9 @@ ch = fluid.make_channel(dtype=INT, buffer_size)
 # Now write three elements to the channel
 with fluid.while(steps=buffer_size):
   fluid.send(ch, step)
-  fluid.close_channel(ch)
-  
+
+fluid.close_channel(ch)
+
 with fluid.while(steps=buffer_size):
   fluid.print(fluid.recv(ch))
 ```
diff --git a/develop/doc_cn/design/csp.html b/develop/doc_cn/design/csp.html
index 954248dab45ec3a4768d452a7497e6ff01f18e36..7b8f00c73cc963a184dd48d40684ddd9e4f7b1bd 100644
--- a/develop/doc_cn/design/csp.html
+++ b/develop/doc_cn/design/csp.html
@@ -344,8 +344,9 @@
 <span class="c1"># Now write three elements to the channel</span>
 <span class="k">with</span> <span class="n">fluid</span><span class="o">.</span><span class="k">while</span><span class="p">(</span><span class="n">steps</span><span class="o">=</span><span class="n">buffer_size</span><span class="p">):</span>
   <span class="n">fluid</span><span class="o">.</span><span class="n">send</span><span class="p">(</span><span class="n">ch</span><span class="p">,</span> <span class="n">step</span><span class="p">)</span>
-  <span class="n">fluid</span><span class="o">.</span><span class="n">close_channel</span><span class="p">(</span><span class="n">ch</span><span class="p">)</span>
-  
+
+<span class="n">fluid</span><span class="o">.</span><span class="n">close_channel</span><span class="p">(</span><span class="n">ch</span><span class="p">)</span>
+
 <span class="k">with</span> <span class="n">fluid</span><span class="o">.</span><span class="k">while</span><span class="p">(</span><span class="n">steps</span><span class="o">=</span><span class="n">buffer_size</span><span class="p">):</span>
   <span class="n">fluid</span><span class="o">.</span><span class="k">print</span><span class="p">(</span><span class="n">fluid</span><span class="o">.</span><span class="n">recv</span><span class="p">(</span><span class="n">ch</span><span class="p">))</span>
 </pre></div>