First of all, you should learn both elective courses and compulsory courses. The difference between the two is that compulsory courses are more important and are the focus of the college entrance examination. Elective courses are selective according to the annual examination. It's very important that the exam outline can't come out. As soon as the outline comes out, you will study in a targeted way. Although there are relatively few elective exams, they are also the focus of study. As for how many schools will arrange it. Do you know what that means?

I studied science. I used to learn everything, but now it's different. You have to weigh the key points and the secondary points yourself. Liberal arts and science are different from those learned later, and science mathematics is more difficult. As for which is more difficult, it is hard to say. What you like is simple, but what you don't like is difficult. Interest in learning is very important. It's much easier to study with interest. ......