No matter whether you go to college or undergraduate, it is best to stay in the library more, and the worst is to soak in internet cafes and do other meaningless things. I want to be a sponge in junior college just because I don't have many classes and I'm not very busy, so I have to consider whether to take the exam or not and whether to learn more. In fact, the junior college is more tired than the undergraduate course, because there is pressure in the exam, and you can ignore it if you don't want to do well in the exam. But since you have said so, I strongly suggest that you get a full mark in CET-4 after three years of junior college. Do you have confidence?