diff --git a/source/component/plant.py b/source/component/plant.py
index 813137c..60d88fe 100755
--- a/source/component/plant.py
+++ b/source/component/plant.py
@@ -1606,9 +1606,9 @@ class DoomShroom(Plant):
 
 # 用于描述毁灭菇的坑
 class Hole(Plant):
-    def __init__(self, x, y, plotType):
+    def __init__(self, x, y, plot_type):
         # 指定区域类型这一句必须放在前面，否则加载图片判断将会失败
-        self.plotType = plotType
+        self.plot_type = plot_type
         Plant.__init__(self, x, y, c.HOLE, c.INF, None)
         self.timer = 0
         self.shallow = False
@@ -1638,9 +1638,9 @@ class Hole(Plant):
         for i, name in enumerate(name_list):
             self.loadFrames(frame_list[i], name)
         
-        if self.plotType == c.MAP_TILE:
+        if self.plot_type == c.MAP_TILE:
             self.frames = self.roof_frames
-        elif self.plotType == c.MAP_WATER:
+        elif self.plot_type == c.MAP_WATER:
             self.frames = self.water_frames
         else:
             self.frames = self.idle_frames
@@ -1649,9 +1649,9 @@ class Hole(Plant):
         if self.timer == 0:
             self.timer = self.current_time
         elif (not self.shallow) and (self.current_time - self.timer >= 90000):
-            if self.plotType == c.MAP_TILE:
+            if self.plot_type == c.MAP_TILE:
                 self.frames = self.roof2_frames
-            elif self.plotType == c.MAP_WATER:
+            elif self.plot_type == c.MAP_WATER:
                 self.frames = self.water2_frames
             else:
                 self.frames = self.idle2_frames
diff --git a/source/constants.py b/source/constants.py
index ceae9c5..6eef56c 100755
--- a/source/constants.py
+++ b/source/constants.py
@@ -180,7 +180,7 @@ SURVIVAL_ROUNDS = "survival_rounds"
 # 地图单元格属性
 MAP_PLANT = "plantnames"
 MAP_SLEEP = "sleep" # 有没有休眠的蘑菇，作是否能种植咖啡豆的判断
-MAP_PLOT_TYPE = "plotType"
+MAP_PLOT_TYPE = "plot_type"
 # 地图单元格区域类型
 MAP_GRASS = "grass"
 MAP_WATER = "water"
diff --git a/source/state/level.py b/source/state/level.py
index 3b2c848..be0370e 100644
--- a/source/state/level.py
+++ b/source/state/level.py
@@ -333,8 +333,8 @@ class Level(tool.State):
         return self.before_pause_time
 
     def initBowlingMap(self):
-        for x in range(3, self.map.width):
-            for y in range(self.map.height):
+        for x in range(3, self.map_x_len):
+            for y in range(self.map_y_len):
                 self.map.setMapGridType(x, y, c.MAP_UNAVAILABLE) # 将坚果保龄球红线右侧设置为不可种植任何植物
 
     def initState(self):
@@ -632,6 +632,8 @@ class Level(tool.State):
     def shovelRemovePlant(self, mouse_pos):
         x, y = mouse_pos
         map_x, map_y = self.map.getMapIndex(x, y)
+        if not self.map.isValid(map_x, map_y):
+            return
         for i in self.plant_groups[map_y]:
             if (x >= i.rect.x and x <= i.rect.right and
                 y >= i.rect.y and y <= i.rect.bottom):
@@ -1082,7 +1084,7 @@ class Level(tool.State):
                         # 默认为最右侧的一个植物
                         target_plant = max(attackable_common_plants, key=lambda i: i.rect.x)
                         map_x, map_y = self.map.getMapIndex(target_plant.rect.centerx, target_plant.rect.centery)
-                        if not (map_x >= self.map.width or map_y >= self.map.height):
+                        if self.map.isValid(map_x, map_y):
                             if c.PUMPKINHEAD in self.map.map[map_y][map_x][c.MAP_PLANT]:
                                 for actual_target_plant in self.plant_groups[i]:
                                     # 检测同一格的其他植物
@@ -1469,6 +1471,8 @@ class Level(tool.State):
         # 铲子接近植物时会高亮提示
         map_x, map_y = self.map.getMapIndex(x, y)
         surface.blit(self.shovel, self.shovel_rect)
+        if not self.map.isValid(map_x, map_y):
+            return
         for i in self.plant_groups[map_y]:
             if (x >= i.rect.x and x <= i.rect.right and
                 y >= i.rect.y and y <= i.rect.bottom):
diff --git a/source/state/screen.py b/source/state/screen.py
index 6837c0c..ea8fd6c 100644
--- a/source/state/screen.py
+++ b/source/state/screen.py
@@ -1,5 +1,6 @@
 import os
 import pygame as pg
+from abc import abstractmethod
 from .. import tool
 from .. import constants as c
 
@@ -7,6 +8,7 @@ class Screen(tool.State):
     def __init__(self):
         tool.State.__init__(self)
 
+    @abstractmethod
     def startup(self, current_time, persist):
         pass