病人男性，24岁，于炎热夏季出现腹泻、腹痛症状，每日腹泻十余次，疑似食用变质食物所致

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send     expensive    waste     problem    cool

Dear headmaster,
I’m a student of Grade 9. I want to tell you something. In our school, many students have mobile phones. They think it’s   1   to have a mobile phone. Yes, the phones let students talk with their parents and friends at any time. But I don’t think it’s good for students to use them at school. Many students spend lots of time in  2   messages by mobile phone, some students even use them to play games in class or cheat (作弊) in the exams. Some students
always hope to buy the new or   3   mobile phones and this will   4   their
parents’ money. And my father tells me that most mobile phones can cause (引起)
many health   5   . Could you do something to stop it?
Yours,
Sophia