diff --git a/W6/AnimalTest.java b/W6/AnimalTest.java
new file mode 100644
index 0000000..b49305e
--- /dev/null
+++ b/W6/AnimalTest.java
@@ -0,0 +1,42 @@
+abstract class Animal {
+    public abstract void makeSound();
+}
+interface Swimmable {
+    void swim();
+}
+class Dog extends Animal implements Swimmable {
+    @Override
+    public void makeSound() {
+        System.out.println("汪汪汪");
+    }
+    @Override
+    public void swim() {
+        System.out.println("狗会游泳");
+    }
+}
+class Cat extends Animal {
+    @Override
+    public void makeSound() {
+        System.out.println("喵喵喵");
+    }
+}
+public class AnimalTest {
+    public static void main(String[] args) {
+        Animal dog = new Dog();
+        Animal cat = new Cat();
+        System.out.println("叫声");
+        dog.makeSound();
+        cat.makeSound();
+        System.out.println("游泳");
+        if (dog instanceof Swimmable) {
+            ((Swimmable) dog).swim();
+        } else {
+            System.out.println("不会游泳");
+        }
+        if (cat instanceof Swimmable) {
+            ((Swimmable) cat).swim();
+        } else {
+            System.out.println("不会游泳");
+        }
+    }
+}
\ No newline at end of file