diff --git a/docs/course/foundation/04_hello_world.md b/docs/course/foundation/04_hello_world.md
index f882a75..aa63268 100644
--- a/docs/course/foundation/04_hello_world.md
+++ b/docs/course/foundation/04_hello_world.md
@@ -53,3 +53,4 @@ print('hello, world!')
 
 
 ### 命令行运行
+