读短文，完成下面的练习。
Lucy always wanted to become a teacher, because she liked children. When she was twenty-one years old, she began(开始) teaching in a small school. She was a good teacher, and she laughed a lot with the children in her class. They liked her teaching.
One day, one of the girls in her class asked her, “Why does a man’s hair become grey(灰白的) before his beard(胡子) does?” Mary laughed and answered, “I don’t know, Helen.” Then one of the boys said, “I know! Men’s hair becomes grey first because it’s sixteen years older than their beard.”
【1】— Why did Lucy want to become a teacher?
— Because she __________________.
【2】—When did Lucy begin to teach?
— She began to teach at _________ years old.
【3】—Did her students like her?
—_________,they _________.
【4】What was the girl’s question?
“Why does a man’s hair ________________________ his beard does?”
【5】How did the boy answer?
He said that their hair was _______ than their _________.
【答案】【1】 liked children
【2】twenty-one
【3】 Yes did
【4】 become grey before
【5】 older beard
【解析】