diff --git a/src/basic/base-type/char-bool.md b/src/basic/base-type/char-bool.md
index af5ad612..788efcd8 100644
--- a/src/basic/base-type/char-bool.md
+++ b/src/basic/base-type/char-bool.md
@@ -24,7 +24,7 @@ fn main() {
 ```rust
 fn main() {
     let x = '中';
-    println!("字符'中'占用了{}字节的内存大小",std::mem::size_of_val(&x));
+    println!("字符'中'占用了{}字节的内存大小", size_of_val(&x));
 }
 ```