补全对话
A: Judy, did you finish your homework?
B:      . But I’m so tired. Let’s relax. What’s your hobby?
A:   
B: Really? What do you collect?
A: I collect stamps and coins.
B:   
A: And you? What do you usually do in your spare time?
B:      I started playing it when I was four.
A: Oh, great!   
B: OK.