Hello. You are asking too much of yourself. Don't do very difficult questions. In particular, the college entrance examination question, the third question about derivatives, really failed, and five points were not needed. The third question of conic curve is really not a five. It's not bad to try to fill in the blanks with 70 points. Usually do more questions and take more notes. If you can't remember, you can ask the teacher for PPT. If you have any problems, you can look at these blackboard books, which are very useful. You can also ask the teacher questions after class. Start (a disease)