Mr Clarke works in a middle school. He likes reading and often1some books from the library. He enjoys2to the radio every morning and reading 3 after supper. So he knows much and teaches well. His 4 worship (崇拜) him very much. Mike, Mr Clarke's little son, is only nine. He5 likes reading books. And he often asks his father some questions. Mr Clarke always thinks he's too 6to understand him and chooses the easiest ones 7. Of course the boy is not happy with it.

    One day Mike reads8about the electric lights (电灯) and is9in it. When his father tells him to do some housework, he is thinking of it. He asks him 10 questions, and his father answers all. Then his father says proudly (自豪地), “Fathers always know more than sons!” The boy thinks11 a while (一会儿) and says,“12 !”

    “Oh? Why?”

    Mike doesn't answer 13 asks instead (反而), “Who invents the electric lights?”

    “Thomas Edison ”answers Mr Clarke.

    “Why doesn't his 14 invent(发明) them, then?”

    Looking at his son, Mr Clarke doesn't know15to answer!