补全对话
A: Hello, Li Lei! What are you doing now?
B: Guess!
A:    
B: Yes, I am.   
A: I’m doing my homework. And I’m going to the school library soon.
B:   
A: Yes, I like the school library best.
B: Why?
A:    What do you like doing best?
B:     I think it’s good for health.