This intensive course is used for short-term surprise attacks. Grammar knowledge points can generally meet the requirements. But other aspects can't be compared with systematic textbooks. For example, vocabulary, sentence patterns, sentence patterns, reading, writing, listening and speaking ability and so on. In addition, the actual teaching quality and publicity of many teaching institutions vary greatly. Therefore, in fact, after reading a book, it can't meet the requirements of the corresponding level. Students need to make more efforts by themselves. Then it is very important to choose a serious and responsible teacher carefully.