补全对话。(30分)
A: （1）____ Can I help you?
B: Yes. I （2）____ a schoolbag.
A: （3）____do you like best?
B: I like the blue one. Its colour is （4）____.
A: All right.（5）____ It is 15 yuan.
B: （6）____ Here is the money. Goodbye.
A: Thank you. Goodbye.
A Which one   B Good morning.   C very beautiful
D Here you are.  E I will take it.  F want to buy