求翻译：不能只明白课本上的习题应怎么做就够了，如果要学好它，就必须在课外再花一些时间来钻研和多做一些试题等。上课仔细听讲是什么意思？

Can not only understand the textbook exercises how to do enough, if you want to learn it, we must spend some time outside the classroom to study and do some questions. Class careful listening

We cannot just understand textbooks on how to do the practice should be enough, if you want to learn it, it must be in extra-curricular to spend some time to study and do some more questions. class attendance carefully

Cannot only understand how in the textbook the exercise should do has sufficed, if had to learn it, had in extracurricular again to spend some time to study diligently and to make some test questions and so on.Attends class listens attentively to a lecture

Not only to understand what exercises should you do is enough of textbooks, if you want to learn it, you must spend some time out of class to do some more research and questions. Carefully in class attendance