diff --git a/pages/docs/advanced/understanding.zh-CN.mdx b/pages/docs/advanced/understanding.zh-CN.mdx
index c01de8dc..9f1fe27a 100644
--- a/pages/docs/advanced/understanding.zh-CN.mdx
+++ b/pages/docs/advanced/understanding.zh-CN.mdx
@@ -120,7 +120,7 @@ function Search() {
   ratio={640/730}
 />
 
-在这里查看完整代码示例：https://codesandbox.io/s/swr-keeppreviousdata-fsjz3m。
+在这里查看完整代码示例：https://codesandbox.io/s/swr-keeppreviousdata-fsjz3m
 
 ## 性能依赖关系收集 [#dependency-collection-for-performance]