How to have a good class?

I agree with you. Are you a student or a teacher? I guess you are usually a student. As a student, if you want to have a good class, you must adhere to the principle of "eyes, heart, ears and hands". The most important thing is that everyone should be here. Hehe, try to follow the teacher's ideas, think hard, ask more questions, consolidate after class and practice asking more questions.