Don't be shy, just be natural and graceful. Needless to say, you should add water to the teacher and then listen carefully when chatting. Occasionally, you can interrupt a few words to communicate with the teacher. Don't be too nervous. In fact, it is easier for teachers to eat out. Plus, you are a student and a child in their eyes, so don't care too much about what you say, just be polite and generous. If you feel bored, you can ask a few better classmates to join you.