Writing prompt: Should Students Be Allowed to Use Cellphone at School?

Student essay:
As time goes by, more and more people have themselves cellphones. That is influence of many students
some advantages are students used cellphone. For one thing, everyone can learn to everywhere and also strengthen communication between parents and children. For another convenient the students learn from each other, everyone can become greatest.
But students used cellphone have some disadvantages also. First, people maybe not used cellphone study. He can play computer games on the phone. Secondly, cellphone is expensive, if break out flood, your parents are argument with you. Thirdly, it is badly for your eyes. If you use a mobile phone for a long time, you will need to wear glasses.
ln my opinion. l think it's better not allowed to students used cellphone

Corrected essay:
As time goes by, more and more people have their own cellphones. That influences many students.
Some advantages exist when students use cellphones. For one thing, everyone can learn anywhere and also strengthen communication between parents and children. For another, it is convenient for students to learn from each other. Everyone can improve greatly.
But students using cellphones also have some disadvantages. First, people may not use cellphones for studying. They can play computer games on the phone. Secondly, cellphones are expensive. If they break, your parents might argue with you. Thirdly, it is bad for your eyes. If you use a mobile phone for a long time, you will need to wear glasses.
In my opinion, I think it's better not to allow students to use cellphones.