diff --git a/IV. Spring Boot features/22. SpringApplication.md b/IV. Spring Boot features/22. SpringApplication.md
index 728e3e7..509530f 100644
--- a/IV. Spring Boot features/22. SpringApplication.md	
+++ b/IV. Spring Boot features/22. SpringApplication.md	
@@ -1,4 +1,4 @@
-### SpringApplication
+###22. SpringApplication
 SpringApplication类提供了一种从main()方法启动Spring应用的便捷方式。在很多情况下，你只需委托给SpringApplication.run这个静态方法：
 ```java
 public static void main(String[] args){