diff --git a/src/main/java/com/example/tankbattle/Bullet.java b/src/main/java/com/example/tankbattle/Bullet.java
index c219a7d..1f68e51 100644
--- a/src/main/java/com/example/tankbattle/Bullet.java
+++ b/src/main/java/com/example/tankbattle/Bullet.java
@@ -11,7 +11,7 @@ public class Bullet extends BaseBullet {
     public static int WIDTH = ResourceMgr.bulletD.getWidth();
     public static int HEIGHT = ResourceMgr.bulletD.getHeight();
 
-    private Rectangle rect = new Rectangle();
+	Rectangle rect = new Rectangle();
 
     private int x, y;
     private Dir dir;
diff --git a/src/main/java/com/example/tankbattle/DefaultFireStrategy.java b/src/main/java/com/example/tankbattle/DefaultFireStrategy.java
index 43ec7a0..aed7746 100644
--- a/src/main/java/com/example/tankbattle/DefaultFireStrategy.java
+++ b/src/main/java/com/example/tankbattle/DefaultFireStrategy.java
@@ -7,7 +7,7 @@ public class DefaultFireStrategy implements FireStrategy {
         int bX = t.x + Tank.WIDTH/2 - Bullet.WIDTH/2;
         int bY = t.y + Tank.HEIGHT/2 - Bullet.HEIGHT/2;
 
-        t.tf.bullets.add(new Bullet(bX, bY, t.dir, t.group, t.tf));
+        new Bullet(bX, bY, t.dir, t.group, t.tf);
 
         if(t.group == Group.GOOD) new Thread(()->new Audio("audio/tank_fire.wav").play()).start();
     }
diff --git a/src/main/java/com/example/tankbattle/Explode.java b/src/main/java/com/example/tankbattle/Explode.java
index 2b3f37d..fd54258 100644
--- a/src/main/java/com/example/tankbattle/Explode.java
+++ b/src/main/java/com/example/tankbattle/Explode.java
@@ -2,7 +2,7 @@ package com.example.tankbattle;
 
 import com.example.tankbattle.abstractfactory.BaseExplode;
 
-import java.awt.*;
+import java.awt.Graphics;
 
 public class Explode extends BaseExplode {
     public static int WIDTH = ResourceMgr.explodes[0].getWidth();
@@ -18,6 +18,8 @@ public class Explode extends BaseExplode {
         this.x = x;
         this.y = y;
         this.tf = tf;
+
+        new Thread(()->new Audio("audio/explode.wav").play()).start();
     }
 
     @Override
diff --git a/src/main/java/com/example/tankbattle/FourDirFireStrategy.java b/src/main/java/com/example/tankbattle/FourDirFireStrategy.java
index 3839859..136a5f0 100644
--- a/src/main/java/com/example/tankbattle/FourDirFireStrategy.java
+++ b/src/main/java/com/example/tankbattle/FourDirFireStrategy.java
@@ -9,7 +9,7 @@ public class FourDirFireStrategy implements FireStrategy {
 
         Dir[] dirs = Dir.values();
         for(Dir dir : dirs) {
-            new Bullet(bX, bY, dir, t.group, t.tf);
+            t.tf.gf.createBullet(bX, bY, dir, t.group, t.tf);
         }
 
         if(t.group == Group.GOOD) new Thread(()->new Audio("audio/tank_fire.wav").play()).start();
diff --git a/src/main/java/com/example/tankbattle/Main.java b/src/main/java/com/example/tankbattle/Main.java
index 72ac5d9..8699bb6 100644
--- a/src/main/java/com/example/tankbattle/Main.java
+++ b/src/main/java/com/example/tankbattle/Main.java
@@ -8,9 +8,11 @@ public class Main {
 
         // 初始化敌方坦克
         for (int i = 0; i < initTankCount; i++) {
-            tf.tanks.add(new Tank(50 + i * 80, 200, Dir.DOWN, Group.BAD, tf));
+            tf.tanks.add(tf.gf.createTank(50 + i * 80, 200, Dir.DOWN, Group.BAD, tf));
         }
 
+        new Thread(() -> new Audio("audio/war1.wav").loop()).start();
+
         while (true) {
             Thread.sleep(50);
             tf.repaint();
diff --git a/src/main/java/com/example/tankbattle/Tank.java b/src/main/java/com/example/tankbattle/Tank.java
index 6468b38..876b4fa 100644
--- a/src/main/java/com/example/tankbattle/Tank.java
+++ b/src/main/java/com/example/tankbattle/Tank.java
@@ -2,7 +2,7 @@ package com.example.tankbattle;
 
 import com.example.tankbattle.abstractfactory.BaseTank;
 
-import java.awt.*;
+import java.awt.Graphics;
 import java.util.Random;
 
 public class Tank extends BaseTank {
@@ -11,22 +11,18 @@ public class Tank extends BaseTank {
     public static int WIDTH = ResourceMgr.goodTankU.getWidth();
     public static int HEIGHT = ResourceMgr.goodTankU.getHeight();
 
-    Rectangle rect = new Rectangle();
-
     private Random random = new Random();
 
-    public int x,y;
+    int x,y;
 
-    public Dir dir = Dir.DOWN;
+    Dir dir = Dir.DOWN;
 
     private boolean moving = true;
 
-    public TankFrame tf = null;
+    TankFrame tf = null;
 
     private boolean living = true;
 
-    public Group group = Group.BAD;
-
     FireStrategy fs;
 
     public Tank(int x, int y, Dir dir, Group group, TankFrame tf) {
@@ -57,7 +53,16 @@ public class Tank extends BaseTank {
     }
 
     public void fire(){
-        fs.fire(this);
+        // fs.fire(this);
+        int bX = this.x + Tank.WIDTH/2 - Bullet.WIDTH/2;
+        int bY = this.y + Tank.HEIGHT/2 - Bullet.HEIGHT/2;
+
+        Dir[] dirs = Dir.values();
+        for(Dir dir : dirs) {
+            tf.gf.createBullet(bX, bY, dir, group, tf);
+        }
+
+        if(group == Group.GOOD) new Thread(()->new Audio("audio/tank_fire.wav").play()).start();
     }
 
     public Dir getDir() {
@@ -103,31 +108,24 @@ public class Tank extends BaseTank {
                 break;
         }
 
-        rect.x = this.x;
-        rect.y = this.y;
-        if (this.group == Group.BAD && random.nextInt(100) > 95) this.fire();
+        if (this.group == Group.BAD && random.nextInt(100) > 95)
+            this.fire();
 
-        if (this.group == Group.BAD && random.nextInt(100) > 95) {
+        if (this.group == Group.BAD && random.nextInt(100) > 95)
             randomDir();
-        }
 
         boundsCheck();
+        //update rect
+        rect.x = this.x;
+        rect.y = this.y;
     }
 
     private void boundsCheck() {
-        if (this.x < 0) {
-            this.x = 2;
-        }
-        if (this.y < 28) {
-            this.y = 28;
-        }
+        if (this.x < 2) x = 2;
+        if (this.y < 28) y = 28;
 
-        if (this.x > TankFrame.GAME_WIDTH - Tank.WIDTH) {
-            this.x = TankFrame.GAME_WIDTH - Tank.WIDTH;
-        }
-        if (this.y > TankFrame.GAME_HEIGHT - Tank.HEIGHT) {
-            this.y = TankFrame.GAME_HEIGHT - Tank.HEIGHT;
-        }
+        if (this.x > TankFrame.GAME_WIDTH - Tank.WIDTH-2) this.x = TankFrame.GAME_WIDTH - Tank.WIDTH - 2;
+        if (this.y > TankFrame.GAME_HEIGHT - Tank.HEIGHT-2) this.y = TankFrame.GAME_HEIGHT - Tank.HEIGHT-2;
     }
 
     private void randomDir() {
diff --git a/src/main/java/com/example/tankbattle/abstractfactory/RectTank.java b/src/main/java/com/example/tankbattle/abstractfactory/RectTank.java
index 90ef8ef..2844bf5 100644
--- a/src/main/java/com/example/tankbattle/abstractfactory/RectTank.java
+++ b/src/main/java/com/example/tankbattle/abstractfactory/RectTank.java
@@ -8,7 +8,6 @@ import com.example.tankbattle.FireStrategy;
 import com.example.tankbattle.Group;
 import com.example.tankbattle.PropertyMgr;
 import com.example.tankbattle.ResourceMgr;
-import com.example.tankbattle.Tank;
 import com.example.tankbattle.TankFrame;
 
 import java.awt.Color;
@@ -138,6 +137,9 @@ public class RectTank extends BaseTank{
             randomDir();
 
         boundsCheck();
+        // update rect
+        rect.x = this.x;
+        rect.y = this.y;
     }
 
     private void boundsCheck() {
@@ -146,10 +148,10 @@ public class RectTank extends BaseTank{
         if (this.y < 28)
             y = 28;
 
-        if (this.x > TankFrame.GAME_WIDTH - Tank.WIDTH)
-            x = TankFrame.GAME_WIDTH - Tank.WIDTH;
-        if (this.y > TankFrame.GAME_HEIGHT - Tank.HEIGHT)
-            y = TankFrame.GAME_HEIGHT - Tank.HEIGHT;
+        if (this.x > TankFrame.GAME_WIDTH - RectTank.WIDTH-2)
+            x = TankFrame.GAME_WIDTH - RectTank.WIDTH;
+        if (this.y > TankFrame.GAME_HEIGHT - RectTank.HEIGHT-2)
+            y = TankFrame.GAME_HEIGHT - RectTank.HEIGHT;
     }
 
     private void randomDir() {