阅读理解。      Mobile phone has become a problem for middle schools. Some middle schools in Australia have
 banned students from carrying mobile phones during school hours.
     Mobile phone use among children has become a problem for the school this year. Several children have
  got mobile phones as Christmas gifts, and more students will want them.
     Mary Bluett, an official, said mobile phone use is a distraction to students during school hours and it
 also gives teachers so much trouble in their classrooms. Teachers were also saying that sometimes
 students might use phone messages to cheat during exams.
     She said some schools had tried to ban mobile phones. Some parents felt unhappy because they
 couldn"t get in touch with their children.
     Many teachers said students should not have mobile phones at school, but if there was a good reason,
 they could leave their phones at school office. They also said there were many reasons why the students
 should not have mobile phones at school; they were easy to lose and were a distraction from studies.
     Many people say that they understand why parents would want their children to have phones, but they
  think schools should let the students know when they can use their mobile phones. 1. Some middle schools in Australia have banned students from carrying mobile phones _____.     A. because they are students
    B. when they are free
    C. when they are at school
    D. because they are children 2. We know from the passage that some children get mobile phones from _____.     A. the makers and sellers
    B. the passers-by and strangers
    C. their parents and friends
    D. some mobile phone users 3. What does the underlined word "cheat" mean in the passage?     A. 聊天
    B. 核对
    C. 查询
    D. 作弊 4. Some parents felt unhappy because they couldn"t _____ during school hours.     A. use their mobile phones
    B. leave their mobile phones at school office
    C. help the teachers with their work
    D. get in touch with their children