完形填空 (共15小题；每小题l分，计15分) Mr Clarke works in a middle school. He likes reading and often some books from the library. He to the radio every morning and reading after supper. So he knows much and teaches well. His worship(崇拜) him very much. Mike, Mr Clarke’s little son, is only nine. He likes reading books. And he often asks his father some questions. Mr Clarke always thinks he's too to understand him and chooses ones to answer. Of course the boy is not satisfied with(对…满意) it. One day Mike read about the electric lights (电灯) and was it. When his father told him to do some housework, he went on thinking of it. He asked him questions, and his father answered all. Then his father said proudly, "Fathers always know than sons!" The boy thought for a while and said," "Oh? Why?" Mike didn’t answer and asked,, "Who invented the electric lights?" "answered Mr Clarke. "Why didn't his father invent them, then?" Looking at his son, Mr Clarke didn't knowto answer!