一个玩笑 A Joke

I am a naughty boy. Yesterday I played a joke on my classmate, Mark. When we all busied doing homework, I draw a picture of dog and wrote a sentence in the bottom,” I am a dog.” And then I carefully put it on the clothes of mark. Mark sat in front of me, so I can make this things achieved easily. When he stood up to answer our teacher’s question next class, everyone saw this and laughed, including the teacher. He felt embarrassed at first, but later he laughed with us. 
我是一个调皮的小男孩。昨天我跟打我的同学，迈克开了一个玩笑。当我们都忙于做作业的时候，我画一只狗并在底部写了一句话，“我是一只狗。”然后我小心翼翼地把它贴到迈克的衣服上。马克坐在我的前面，所以我很容易地就把事情做好了。当下节课他站起来回答老师，每个人都看见了，也都笑了，包括老师也笑了。他一开始感到很尴尬，但后来他也和我们一起笑了。