Xiaoyou's suggestions are: first, summarize the knowledge points you don't understand, and find a teacher to answer them after class or in your spare time. Second, classify similar problems and see if similar problems have the same problems. Many times we can find the answer in similar questions. Third, make a list of knowledge points that you don't understand. Many times, as soon as the teacher speaks, you will understand the difficulty. Pay attention to the winning education "Sichuan College-upgraded Newsletter" to get more information about college-upgraded books and prepare dry goods.