Mathematics is a very logical subject, so the foundation is more important. Pay attention to the class and ask the teacher or classmates in time if you don't understand. Don't think that there is only one problem unsolved, because this knowledge point will continue to be used in future study, and then it will not be an unsolvable problem, and then it will become two or three ... and it will accumulate more and more. The knowledge points you have learned should be reviewed in time and you can consolidate your knowledge by doing exercises. In this way, mathematics is very difficult to learn!