When Mary Smith was a middle school student, she always wanted to become a teacher because she liked children very much. When she was twenty-one years old, she began to teach in a primary school. She liked her job very much and she was certainly a very good teacher and she got on well with her students in her class. And all the students in her class regarded (把……看作) her as their good friends.

　　One day, one of the girls in her class asked her, “Miss Smith, why does a man's hair become gray much earlier than his mustache and beard?”

　　Mary smiled and said, “I'm sorry I don't know. Is it true that a man's hair becomes gray earlier than his mustache and beard?”

　　“Yes. Miss Smith.” answered the girl Helen. “It has happened to my father.” Hearing this the other children in the class all laughed at the silly (傻里傻气的) girl. And the girl felt very nervous and cried.

　　Just before Miss Smith wanted to say something to the girl, one of the boys put up his hand and said, “I know, Miss Smith. Men's hair becomes gray first just because it's sixteen years older than their mustaches and beards.”

　　“Good answer! Who can give another answer? Or we can have a discussion (讨论).”

　　“I want to say men have hair when they were born. But when they grow up they begin to wear mustaches and beards. That's my father told me!” A fat girl answered quickly.

　　After the students heard these two answers, they all laughed again.

　　“OK. You gave the same answer to Helen's question. How clever you are! Thank you very much. And I want to say if we want to know the exact answer we must work hard at all subjects and then we can learn many useful things about our bodies and life and so on. And we can ask an expert (专家) about this question.”

(1) Mary decided to ________ when she was young because she loved children.

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(2) Miss Smith was a very good teacher because she ________.

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A．loved her work

B．was very young

C．got on well with her students

D．both A and C

(3) Helen's question was ________ for the teacher to answer.

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(4) The students in Mary's class were very ________.

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(5) Which of the following is right?

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A．Helen asked the silly question to make Mary angry.

B．The students didn't like Miss Smith.

C．The children couldn't answer the question.

D．Helen's father had gray hair.