diff --git a/doc/c#stupid.md b/doc/c#stupid.md
index 7505eaf..049f5ab 100644
--- a/doc/c#stupid.md
+++ b/doc/c#stupid.md
@@ -1,5 +1,5 @@
 
-# C# stupid to i can't understand，and UI programming.
+# C# is too stupid to understand，and UI programming.
 # C#愚蠢到我不能理解，兼论UI构造方法。
 
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