答案優(yōu)選We shouldn't allow college students to use mobile phones. There are several reasons. First, we won't listen to the teachers carefully in class. If we use mobile phones, we will often send text messages to each other, even in class. That will affect the efficiency of having classes. Second, we won't have enough sleep. Some of us use mobile phones too often. They even use it to send text messages even it is time to go to bed. This will influence their sleeping efficiency. If we don't have enough sleep, we will fall asleep while we are having classes. Finally, we won't talk to each other face to face often. If we talk to others on mobile phones, we don't know how to deal with people face to face. That will be terrible, because we have to face people, esp when we are finding jobs. We have a lot of interviews. If we don't know how to talk with people face to face, we will fail to find jobs. That's why we don't allow college students to use mobile phones.