diff --git a/w6/Animal.java b/w6/Animal.java
new file mode 100644
index 0000000..5482c89
--- /dev/null
+++ b/w6/Animal.java
@@ -0,0 +1,32 @@
+// 抽象类 Animal
+abstract class Animal {
+    public abstract void makeSound();
+}
+
+// 接口 Swimmable
+interface Swimmable {
+    void swim();
+}
+
+// Dog 类继承 Animal 并实现 Swimmable
+class Dog extends Animal implements Swimmable {
+    @Override
+    public void makeSound() {
+        System.out.println("狗叫：汪汪汪！");
+    }
+
+    @Override
+    public void swim() {
+        System.out.println("狗会游泳，正在狗刨...");
+    }
+}
+
+// Cat 类继承 Animal，不实现 Swimmable
+class Cat extends Animal {
+    @Override
+    public void makeSound() {
+        System.out.println("猫叫：喵喵喵~");
+    }
+}
+
+
diff --git a/w6/AnimalTest.java b/w6/AnimalTest.java
new file mode 100644
index 0000000..8619fc4
--- /dev/null
+++ b/w6/AnimalTest.java
@@ -0,0 +1,21 @@
+// 测试类
+public class AnimalTest {
+    public static void main(String[] args) {
+        // 多态调用
+        Animal dog = new Dog();
+        Animal cat = new Cat();
+
+        dog.makeSound();
+        cat.makeSound();
+
+        // 判断 Dog 是否实现了 Swimmable 接口并调用
+        if (dog instanceof Swimmable) {
+            ((Swimmable) dog).swim();
+        }
+
+        // Cat 不能游泳
+        if (!(cat instanceof Swimmable)) {
+            System.out.println("猫不会游泳");
+        }
+    }
+}