Doing problems is on the one hand, mainly thinking. You must think of a good way to do this problem. No books, no examples. If you don't practice, you won't. When you encounter a problem you have done, you can easily do it, and your level will not be low. Make sure that you can work out the questions you have done independently, and you don't need to turn to the books to see the answers. If you still have questions to do, do them yourself and see the answers. If you do too much, don't do it. Don't do the problem just to finish the task, but for yourself. Mathematics in the college entrance examination is actually not very difficult. As long as you ensure that you can make no mistakes, your score must be very high.