I am in the seventh grade, too. If you find the question difficult, you should do it all the more. When we learn how to check and write prescriptions in the second grade, you should lay a good foundation, or you will regret it. Now every problem is an exercise, which is really difficult. You should explain to the teacher and ask him to help you. First, if a teacher only asks you to do and doesn't help you with the questions you can't do, then he is not a teacher. Second, you should have the enthusiasm for learning. Think for yourself whether to do it or not.