diff --git a/public/docs/ts/latest/guide/pipes.jade b/public/docs/ts/latest/guide/pipes.jade
index a17032d3cd..eb465ae925 100644
--- a/public/docs/ts/latest/guide/pipes.jade
+++ b/public/docs/ts/latest/guide/pipes.jade
@@ -564,6 +564,9 @@ a#impure-flying-heroes
     我们可以在<live-example></live-example>中确认，当我们输入新的英雄甚至修改#[code heroes]数组时，这个#[i 会飞的英雄]的显示也跟着更新了。
 
 h3#async-pipe The impure #[i AsyncPipe]
+
+h3#async-pipe 非纯#[i AsyncPipe]
+
 :marked
   The Angular `AsyncPipe` is an interesting example of an impure pipe.
   The `AsyncPipe` accepts a `Promise` or `Observable` as input