We all have certain kinds of bad habits. For teenagers, it is very important to get rid of bad habits.
Let's take the habits of talking in class as an example. If we talk in class, we can't listen to the teachers carefully. Of course we can't understand the teachers, and can't finish our homework easily after class. Some students have to copy others' homework when the teachers ask us to hand it in. Then we will get weak in our school lessons and we will become a bad student in the teachers' eyes. Besides, talking in class maybe influences some other students.
So, we must get rid of bad habits at once.
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我们都有各种各样的坏习惯。对于青少年来说，改掉这些坏习惯是非常重要的。
让我们以上课说话为例。如果我们上课说话，我们就不能注意听讲，当然不能很好的理解老师所讲的内容，课后就不能轻易完成老师的作业。当老师要求我们交作业时，一些同学不得不去抄袭其他同学的作业。然后我们的功课会变得很差，我们将会变成一个老师眼中的坏学生。不仅如此，在上课说话还会影响其他的学生。
因此，我们必须立刻改掉坏习惯。