补全对话。
A: What's that under the tree?
B: It's (1)_____ bike.
A: (2)_____(3)_____ new?
B: Yes, it is. It's a nice (4)_____.
A: (5)_____ is it?
B: I (6)_____(7)_____ Lucy's. Let's go and (8)_____ her. Hi, Lucy. Is this bike (9)_____?
C: (10)_____, it is.
A: Lucy, you must (11)_____(12)_____ it.
C: OK. Thanks.