diff --git a/docs/let.md b/docs/let.md
index 78184f1..26dfb81 100644
--- a/docs/let.md
+++ b/docs/let.md
@@ -156,13 +156,13 @@ let不允许在相同作用域内，重复声明同一个变量。
 
 ```javascript
 // 报错
-{
+function () {
   let a = 10;
   var a = 1;
 }
 
 // 报错
-{
+function () {
   let a = 10;
   let a = 1;
 }