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（），mobile phones are being more and more widely used.It′s small in size，（），offering fast and convenient service for communication.It′s of multi-function.（）.
In recent years，（），Quite a few use them at school to keep in touch with their families and friends instead of writing letters，which，of course brings convenience to them.But I don′t think it′s good to do so.
（），student users often waste a lot of time chatting over the phone in their spare time，some even use them to cheat in exams.In addition，mobile phone bill is also a heavy burden on students′families.