As we all know,class is place where students ought to work harder to realize their dreams. However,there are some students not using class properly,which makes things to go from bad to worse. For example,some students play mobile phones and sleep in class,wasting quantities of precious time. What's worse,some students enjoy chat with others. Not only does it affect our own study,but also it will do harm for others.
As far as I am concern,the main reason is that they don't realize the importance of study. To solve this problem,they have to understand making full use of class was the best way to improve the efficiency of study. After all,time and tide waits for no man.