Wu Bing was a tall boy. He liked sports very much. He didn't do well in his lessons. He was often asleep in class. He was the naughtiest（淘气的）boy in his class.

　　He would have a biology（生物）lesson next class. Wu Bing knew that his biology teacher was nearsighted（近视的）. He took off his coat and put it on his desk. Then he took Li Lei's seat. Li Lei wasn't here because he was ill. Wu Bing's seat was at the back of the classroom and Li Lei's was in the middle.

　　When the bell rang, the teacher came in.”Good afternoon, class,”said Mr. Zhang.”We are going to learn a new lesson in this class. But before that, You'd review（复习）our lessons. Now, please answer my question. Why are bears often asleep for about six months in winter?”

　　“Li Lei, could you tell me the answer?”asked Mr. Zhang and he looked at Wu Bing. Wu Bing had to stand up and answered,”Because no one dares（敢）to wake them up.”All the students laughed.

　　The teacher shook his head and said,“You are a good student, I think. But please get ready to answer my questions next time. Now, You'd begin the new lesson.”

　　The teacher looked around and found that Wu Bing was asleep. He became very angry.”Don't sleep in class, Wu Bing. If you don't look at me, you won't know what a hippo（河马）looks like.”All the students laughed again.

　　Wu Bing stood up and said,”I'm sorry, Mr. Zhang. I'm not asleep. I'm here. That's my coat”. The teacher and the students laughed loudly.