完型填空
John is a famous writer now. But he said he was not a good student when he was young. He was often late for _________ and didn’t like doing his homework. Sometimes, he slept in class while the teacher was teaching. He didn’t understand much, _______ he always thought he understood everything. One day the teacher asked the students a question. “When Jack was ten years old, _________ brother Bob was twenty. Jack is fifteen now and how old is Bob?” John said, “That’s easy. Bob is ________ as old as Jack, so he is now thirty.
Another time, the teacher in a science class asked, “When it thunders(雷电), ________ do we always see the light before we hear the sound?”
“But, Miss,” said John______, “Don’t you know our eyes are in front of our ears?”

A．sleep B．lunch C．class D．play

A．so B．and C．or D．but

A．your B．my C．his D．her

A．twice B．just C．not D．only

A．what B．when C．where D．why

A．quickly B．safely C．recently D．really