更改了语法

zh/02.3.md

@@ -149,22 +149,22 @@ Go里面最强大的一个控制逻辑就是`for`，它即可以用来循环读
 
 	integer := 6
 	switch integer {
-		case 4:
+	case 4:
 		fmt.Println("The integer was <= 4")
 		fallthrough
-		case 5:
+	case 5:
 		fmt.Println("The integer was <= 5")
 		fallthrough
-		case 6:
+	case 6:
 		fmt.Println("The integer was <= 6")
 		fallthrough
-		case 7:
+	case 7:
 		fmt.Println("The integer was <= 7")
 		fallthrough
-		case 8:
+	case 8:
 		fmt.Println("The integer was <= 8")
 		fallthrough
-		default:
+	default:
 		fmt.Println("default case")
 	}