Two days ago,I receive your email saying that you were unhappy at being punished for just using your cellphone in class. It's true that the cellphone plays a important part in our daily life .It is of great ues to us though it can heip us in many way.Especially when something urgent happen,the phone,with that we can get immediate help easily,can real make a difference . Besides ,it is very convenient for us to get touch with others.But as a student,use your cellphone in class disturbs you