If the foundation is not very good, it is suggested to read the information in advance before class (similar to the principle formula and example on May 3), and recite the above principle formula before doing the example, so that you will not listen to the gobbledygook in class. I suggest reading more materials, memorizing the formula and then understanding the examples, so that you can basically grasp the basic points.
If the foundation is good, it is recommended to brush more papers. Brushing papers is a bit tiring, but it is really useful for exams. If you brush the paper on the basis of getting the basic score, the speed will be improved and the quality of answering questions will be improved.