One possible version:
Dear principle,
I’m writing to tell you about the discussion we’ve had about whether a mobile phone should be brought to school.
To tell you the truth, the students in our class have different opinions.About 70% of the students think that we shouldn’t bring mobile phones to school. Because with them we may not fix our attention to the lessons. If the phone is not turned off by chance and the ringing will destroy the class. Furthermore, using mobile phones will add to our parents’ economic burdens. However,about 30% of the students think we can bring phones to school on condition that we turned off them in class. With a mobile phone it is convenient for us to keep in touch with our parents and friends.Besides,the mobile phone is a tool of information times. It may not be right to ban students from carrying mobile phones.
Yours sincerely,
Li Hua
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