Hehe, first of all, I want to tell you. Of course, it's difficult to get high numbers, whether you study A\B\C\D\ or E, but I want to tell you that high numbers are actually very simple. As long as you listen carefully in class, you can do some exercises and take notes after class. There should be no problem. As for the practice with high school mathematics. I don't know if you are a black market science student in liberal arts. Liberal arts students may be a little tired, because you only study derivatives and probably have never studied integrals. Science students may get a little into the state. Let's go But in general, if you want to use the knowledge of high school to deal with advanced mathematics, it is a bit difficult. As I said above, if you want to learn advanced mathematics well, you must listen carefully in class, take notes in class and do more exercises after class. As long as you ask those who are good at high numbers, they will say they are "doing". This is the only shortcut to learn advanced mathematics well. I hope the above will help you.