diff --git a/w6/Animal.java b/w6/Animal.java
new file mode 100644
index 0000000..f6d0aa5
--- /dev/null
+++ b/w6/Animal.java
@@ -0,0 +1,19 @@
+package com.rental.animal;
+
+public abstract class Animal {
+    private String name;
+    
+    public Animal(String name) {
+        this.name = name;
+    }
+    
+    public String getName() {
+        return name;
+    }
+    
+    public void setName(String name) {
+        this.name = name;
+    }
+    
+    public abstract void makeSound();
+}
\ No newline at end of file
diff --git a/w6/AnimalTest.java b/w6/AnimalTest.java
new file mode 100644
index 0000000..d2d4efe
--- /dev/null
+++ b/w6/AnimalTest.java
@@ -0,0 +1,36 @@
+package com.rental.animal;
+
+public class AnimalTest {
+    public static void main(String[] args) {
+        System.out.println("===== 多态测试 =====\n");
+        
+        Animal dog = new Dog("旺财");
+        Animal cat = new Cat("小白");
+        
+        System.out.println("测试 makeSound 方法（多态调用）：");
+        dog.makeSound();
+        cat.makeSound();
+        
+        System.out.println("\n===== 测试游泳能力 =====\n");
+        
+        if (dog instanceof Swimmable) {
+            ((Swimmable) dog).swim();
+        }
+        
+        if (cat instanceof Swimmable) {
+            ((Swimmable) cat).swim();
+        } else {
+            System.out.println(cat.getName() + "不会游泳");
+        }
+        
+        System.out.println("\n===== 动物数组测试 =====\n");
+        
+        Animal[] animals = {new Dog("大黄"), new Cat("小花"), new Dog("黑子")};
+        for (Animal animal : animals) {
+            animal.makeSound();
+            if (animal instanceof Swimmable) {
+                ((Swimmable) animal).swim();
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/w6/Cat.java b/w6/Cat.java
new file mode 100644
index 0000000..5dbf31d
--- /dev/null
+++ b/w6/Cat.java
@@ -0,0 +1,13 @@
+package com.rental.animal;
+
+public class Cat extends Animal {
+    
+    public Cat(String name) {
+        super(name);
+    }
+    
+    @Override
+    public void makeSound() {
+        System.out.println(getName() + "喵喵叫");
+    }
+}
\ No newline at end of file
diff --git a/w6/Dog.java b/w6/Dog.java
new file mode 100644
index 0000000..fc59af4
--- /dev/null
+++ b/w6/Dog.java
@@ -0,0 +1,18 @@
+package com.rental.animal;
+
+public class Dog extends Animal implements Swimmable {
+    
+    public Dog(String name) {
+        super(name);
+    }
+    
+    @Override
+    public void makeSound() {
+        System.out.println(getName() + "汪汪叫");
+    }
+    
+    @Override
+    public void swim() {
+        System.out.println(getName() + "在游泳");
+    }
+}
\ No newline at end of file
diff --git a/w6/Swimmable.java b/w6/Swimmable.java
new file mode 100644
index 0000000..6e3089c
--- /dev/null
+++ b/w6/Swimmable.java
@@ -0,0 +1,5 @@
+package com.rental.animal;
+
+public interface Swimmable {
+    void swim();
+}
\ No newline at end of file