Nonsense, of course, there must be certain rules! But the coach will definitely tell you the rules. Some instructors speak poor Mandarin, so it's normal that you can't hear clearly. But remember, in the army, there are only wrong actions and no wrong passwords. In other words, although the instructor is wrong, he must be right. You must do what he says. Limited time is to exercise you. You're not used to it. When you get used to it, you will feel in good order!