If you can get online, search online more. University teachers don't urge them like middle school teachers. If the internet is inconvenient, they borrow books from the library. Extracurricular books are essential. Even if you do this, it's hard to learn well. The most important thing is to understand the homework. After all, you may not be a physics major, and there are often examination questions in your homework. If the school deliberately collects make-up exam fees for income, then the difficulty of the exam questions can be imagined. You know, you must get on well with the teacher. . . I hope it helps you.