diff --git a/day09/src/com/inmind/extend01/test/Animal.java b/day09/src/com/inmind/extend01/test/Animal.java
new file mode 100644
index 0000000..691dfba
--- /dev/null
+++ b/day09/src/com/inmind/extend01/test/Animal.java
@@ -0,0 +1,11 @@
+package com.inmind.extend01.test;
+
+public class Animal {
+    String name;
+    int age;
+    String color;
+
+    public void eat(){
+        System.out.println("到点了，该吃饭了");
+    }
+}
diff --git a/day09/src/com/inmind/extend01/test/Cat.java b/day09/src/com/inmind/extend01/test/Cat.java
new file mode 100644
index 0000000..caa3460
--- /dev/null
+++ b/day09/src/com/inmind/extend01/test/Cat.java
@@ -0,0 +1,7 @@
+package com.inmind.extend01.test;
+
+public class Cat extends Animal{
+    public void catchMouse(){
+        System.out.println("猫能抓老鼠");
+    }
+}
diff --git a/day09/src/com/inmind/extend01/test/Demo02.java b/day09/src/com/inmind/extend01/test/Demo02.java
index 847f051..398f68d 100644
--- a/day09/src/com/inmind/extend01/test/Demo02.java
+++ b/day09/src/com/inmind/extend01/test/Demo02.java
@@ -11,4 +11,21 @@ package com.inmind.extend01.test;
 创建猫和狗对象，设置属性，并调用各自的方法
  */
 public class Demo02 {
+    public static void main(String[] args) {
+        //创建一只狗
+        Dog dog = new Dog();
+        dog.name = "小黄";
+        dog.age = 1;
+        dog.color = "黄色";
+        dog.eat();
+        dog.watchDoor();
+
+        //创建一只猫
+        Cat cat = new Cat();
+        cat.name = "小白";
+        cat.age = 2;
+        cat.color = "白色";
+        cat.eat();
+        cat.catchMouse();
+    }
 }
diff --git a/day09/src/com/inmind/extend01/test/Dog.java b/day09/src/com/inmind/extend01/test/Dog.java
new file mode 100644
index 0000000..fb8b344
--- /dev/null
+++ b/day09/src/com/inmind/extend01/test/Dog.java
@@ -0,0 +1,8 @@
+package com.inmind.extend01.test;
+
+public class Dog extends Animal{
+
+    public void watchDoor(){
+        System.out.println("狗在看门");
+    }
+}