What should I do if I didn't listen carefully in the final exam of the Outline of Modern History in China for one semester?
Don't worry about this at all. It's a simple course and the exam is easy. As long as you read the main points drawn by the teacher from the classmate's textbook, and then take some time to read them, you can. There is absolutely no need to worry about this kind of course. I strongly suggest that you skip this kind of ideological and political course next semester. You can take time out to study other things and read books that interest you, but if you play games during your skipping class, you'd better go to class.