diff --git a/my_Tetris.py b/my_Tetris.py
index c7a09eb..be5ac31 100644
--- a/my_Tetris.py
+++ b/my_Tetris.py
@@ -8,6 +8,8 @@ grid_size = 20  # 格子大小
 grid_num_width = 15     # 横向格子数量
 grid_num_height = 25      # 纵向格子数量
 FPS = 30
+states =False
+count=0
 
 # 创建窗口
 screen = pygame.display.set_mode((460, 500))
@@ -45,15 +47,6 @@ cube_colors = [
     (255, 204, 0), (204, 0, 51),(255, 0, 51), (0, 102, 153),
     (153, 0, 51), (204, 255, 102), (255, 153, 0)]
 
-center = [2, 8]     # 第2行第8列
-
-#随机取出一个形状里的随机一个方向
-shape = random.choice(shape_list)
-index = random.randint(0,len(shape)-1)
-current_shape = shape[index]
-#随机颜色
-color =random.choice(cube_colors) 
-
 def check(center):
     for cube in current_shape:
         cube = (cube[0]+center[0],cube[1]+center[1])
@@ -68,16 +61,40 @@ while True:
             exit()
         if event.type == locals.KEYDOWN:
             if event.key == locals.K_RIGHT:     # 向右
-                if center[1] < 15:
-                    center[1] += 1
+                center[1] += 1
+                if check(center) == False:
+                    center[1]-=1
             elif event.key == locals.K_LEFT:    # 向左
                 center[1] -= 1
                 if check(center) == False:
                     center[1]+=1
             elif event.key == locals.K_DOWN:    # 向下
-                if center[0] < 25:
-                    center[0] += 1
-
+                center[0] += 1
+                if check(center) == False:
+                    center[0]-=1
+            elif event.key == locals.K_UP:
+                old_index = index
+                index+=1
+                if index>=len(shape):
+                    index=0
+                current_shape=shape[index]
+                if check(center) == False:
+                    index= old_index
+                    current_shape=shape[index]
+    if states==False:
+        states=True                
+        center = [2, 8]     # 第2行第8列    
+        shape = random.choice(shape_list) #随机取出一个形状里的随机一个方向
+        index = random.randint(0,len(shape)-1)
+        current_shape = shape[index]
+        #随机颜色
+        color =random.choice(cube_colors) 
+    count+=1
+    if count%FPS==0:
+        center[0] += 1
+        if check(center) == False:
+            center[0]-=1
+            states=False
     # 将背景图画上去
     screen.blit(background, (0, 0))
     # 计算出所有小方块的行、列位置