diff --git a/Demo/LCActionSheetDemo/ViewController.m b/Demo/LCActionSheetDemo/ViewController.m
index e992485..2371d54 100644
--- a/Demo/LCActionSheetDemo/ViewController.m
+++ b/Demo/LCActionSheetDemo/ViewController.m
@@ -103,7 +103,7 @@ - (IBAction)showBlockActionSheet {
         NSMutableIndexSet *set = [[NSMutableIndexSet alloc] init];
         [set addIndex:1];
         [set addIndex:2];
-        [actionSheet appendButtonsWithTitles:@[@"Hello", @"World"] atIndexes:set];
+        [actionSheet appendButtonsWithTitles:@[@"Hello", @"World"] atIndexSet:set];
     });
 }
 
diff --git a/README.md b/README.md
index c56fc8f..a35e95e 100644
--- a/README.md
+++ b/README.md
@@ -141,7 +141,7 @@ In me the tiger sniffs the rose.
         NSMutableIndexSet *set = [[NSMutableIndexSet alloc] init];
         [set addIndex:1];
         [set addIndex:2];
-        [actionSheet appendButtonsWithTitles:@[@"Hello", @"World"] atIndexes:set];
+        [actionSheet appendButtonsWithTitles:@[@"Hello", @"World"] atIndexSet:set];
     });
     
     [actionSheet show];
@@ -283,37 +283,41 @@ In me the tiger sniffs the rose.
 
   ```objc
   @interface LCActionSheet : UIView
-
+  
   // Append button at index with title.
   - (void)appendButtonWithTitle:(nullable NSString *)title atIndex:(NSUInteger)index;
-
+  
   // Append buttons at indexes with titles.
-  - (void)appendButtonsWithTitles:(NSArray<NSString *> *)titles atIndexes:(NSIndexSet *)indexes;
-
+  - (void)appendButtonsWithTitles:(NSArray<NSString *> *)titles atIndexSet:(NSIndexSet *)indexSet;
+  
   @end
   ```
 
 * 修改属性类型：
 
   ```objc
+  @interface LCActionSheet : UIView
+  
   @property (nullable, nonatomic, strong) NSSet<NSNumber *> *destructiveButtonIndexSet;
-
+  
   // ->
-
+  
   @property (nullable, nonatomic, strong) NSIndexSet *destructiveButtonIndexSet;
+
+  @end
   ```
 
 * 修改方法命名：
 
   ```objc
   @interface LCActionSheet : UIView
-
+  
   - (void)appendButtonTitles:(nullable NSString *)buttonTitles, ... NS_REQUIRES_NIL_TERMINATION;
-
+  
   // ->
-
+  
   - (void)appendButtonsWithTitles:(nullable NSString *)titles, ... NS_REQUIRES_NIL_TERMINATION;
-
+  
   @end
   ```
 
diff --git a/Sources/LCActionSheet.h b/Sources/LCActionSheet.h
index 2fecea1..a66c92d 100644
--- a/Sources/LCActionSheet.h
+++ b/Sources/LCActionSheet.h
@@ -376,10 +376,10 @@ typedef void(^LCActionSheetDidDismissHandler)(LCActionSheet *actionSheet, NSUInt
 /**
  Append buttons at indexes with titles.
 
- @param titles  titles
- @param indexes indexes
+ @param titles   titles
+ @param indexSet indexSet
  */
-- (void)appendButtonsWithTitles:(NSArray<NSString *> *)titles atIndexes:(NSIndexSet *)indexes;
+- (void)appendButtonsWithTitles:(NSArray<NSString *> *)titles atIndexSet:(NSIndexSet *)indexSet;
 
 /**
  Show the instance of LCActionSheet.
diff --git a/Sources/LCActionSheet.m b/Sources/LCActionSheet.m
index 31ebcbc..4506851 100644
--- a/Sources/LCActionSheet.m
+++ b/Sources/LCActionSheet.m
@@ -389,16 +389,16 @@ - (void)appendButtonWithTitle:(NSString *)title atIndex:(NSUInteger)index {
     [self updateTableView];
 }
 
-- (void)appendButtonsWithTitles:(NSArray<NSString *> *)titles atIndexes:(NSIndexSet *)indexes {
+- (void)appendButtonsWithTitles:(NSArray<NSString *> *)titles atIndexSet:(NSIndexSet *)indexSet {
 #ifdef DEBUG
-    NSAssert(titles.count == indexes.count, @"Count of titles differs from count of indexs");
+    NSAssert(titles.count == indexSet.count, @"Count of titles differs from count of indexs");
 #endif
     
     NSMutableIndexSet *indexSetM = [[NSMutableIndexSet alloc] init];
-    [indexes enumerateIndexesUsingBlock:^(NSUInteger idx, BOOL * _Nonnull stop) {
+    [indexSet enumerateIndexesUsingBlock:^(NSUInteger idx, BOOL * _Nonnull stop) {
 #ifdef DEBUG
         NSAssert(idx != 0, @"Index 0 is cancel button");
-        NSAssert(idx <= self.otherButtonTitles.count + indexes.count, @"Index crossed");
+        NSAssert(idx <= self.otherButtonTitles.count + indexSet.count, @"Index crossed");
 #endif
         
         [indexSetM addIndex:idx - 1];