diff --git a/my_Tetris.py b/my_Tetris.py
index d1dd9d2..dcb43e4 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
+cctv = 0
+ddtv = True
 
 # 创建窗口
 screen = pygame.display.set_mode((460, 500))
@@ -57,15 +59,22 @@ while True:
                             center[1] += 1
                             break
             elif event.key == locals.K_UP:  
-                kxm = k  # 向下
+                kxm = k  
                 k += 1
                 if k >= len(a):
                     k = 0
                 for i in current_pos:
-                    if i[1] == 0 or i[1] == 14:
+                    if i[1] == 0 or i[1] == 14 or i[0] == 25:
                         k = kxm
                 b = a[k]
-
+            elif event.key == locals.K_DOWN:
+                if center[0] < 25:
+                    center[0] += 1
+                    for i in current_pos:
+                        if i[0]==25:
+                            center[0] -= 1
+                            ddtv = True
+                            break
     # 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
@@ -81,5 +90,26 @@ while True:
     text_surface = font.render(str(score), True, (0, 0, 0))
     screen.blit(text_surface, (350,70))
     # 刷新画面
+
+    if ddtv == True:
+        ddtv = False
+        center = [2, 8]     # 第2行第8列
+        a = random.choice(shape_list)
+        k = random.randint(0,len(a)-1)
+        b = a[k]
+        f = random.choice(cube_colors)
+
+
+    if cctv % 30 ==  0:
+        if center[0] < 25:
+            center[0] += 1
+            for i in current_pos:
+                if i[0]==25:
+                    center[0] -= 1
+                    ddtv = True
+                    break
+
+    cctv += 1
+
     pygame.display.update()
-    clock.tick(FPS)
+    clock.tick(FPS)
\ No newline at end of file