Mr. Clarke works in a middle school. He likes reading and often1 some books from the library. He2 to the radio every morning and reads3 after dinner. So he knows much and teaches well. His4 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. But Mr. Clarke always. thinks the boy is too. 6 to understand so he chooses7 ones to answer. Of course the boy is not satisfied(满意的)with it.
One day,Mike8 something about the electric lights (电灯)and is9 it.
When his father tells him to do some housework,the son goes on thinking of it. He asks the father a few questions,and his father answers10 .
Then his father says proudly(自豪地),"Fathers always know11 than sons!"
The boy thinks fora while and says,"12 . "
Mike doesn't answer but asks13 "Who invented(发明)the electric lights?"
"Thomas Edison. " answers Mr. Clarke.
"Why didn't his14 invent them,then?"
Looking at his son,Mr. Clarke doesn't know15 to answer it.