It is certain to do the problem, but do it effectively, not blindly, and learn to sum up experience when doing it. For example, if you can really do this problem, you should know what you don't know, and you should know where you are weak and need to strengthen. The application problem is nothing more than the change and synthesis of the foundation, so the foundation must be solid first, and you must forget to read it, so you must do the exercises selectively first. Generally speaking, study exams are nothing more than those questions changing. If you can't do it in the regular exam, you must understand it, even if it takes a long time. You know, once you can do that most feared problem, you won't be afraid anymore, and your strength has also risen to a higher level, which is very precious. If you can do one plus one, but you are still practicing the same similar problem over and over again, you won't keep doing it. . . . . .