填空题 阅读下面短文，选择合适的内容将短文补充完整。（），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.

单项选择题 What kind of mistake did Tom make？（）

单项选择题 The shop Tom went into sold（）.