diff --git a/ch2/2.1/ObjC/HelloWorld/HelloWorld/ViewController.m b/ch2/2.1/ObjC/HelloWorld/HelloWorld/ViewController.m
index 6250566..7a1377f 100755
--- a/ch2/2.1/ObjC/HelloWorld/HelloWorld/ViewController.m
+++ b/ch2/2.1/ObjC/HelloWorld/HelloWorld/ViewController.m
@@ -11,7 +11,7 @@
 //  QQ：569418560 邮箱：eorient@sina.com
 //  QQ交流群：162030268
 //
-
+//修改
 #import "ViewController.h"
 
 @interface ViewController ()