I learned abstract concepts in the second day of junior high school, including points. I also learned it quickly. Now in the third grade, I have some opinions: the concepts in the book must be read more, which is very different from junior high school! The second is the proof in the book, which is dead! I didn't learn the content of high school at first, but I learned to substitute. Lagrange didn't understand it for three hours. Keep reading … it's not the most important thing to understand, but you must have the determination to understand until you don't understand! The third is to do the problem! Different from junior high school, most of the problems can be said to be "difficult problems" in junior high school (corresponding to a junior high school student). What I do is junior high school content. Except for some competitions, I don't seem to feel that I am reasoning and thinking, but the university content is different, thinking and thinking constantly. One more thing, maybe this topic is useless … priority! The senior high school entrance examination is the most important! It is the most important thing to get into a good high school!