在方框中选择适当的选项补全对话，其中有一项是多余的。

A. What's in the bag? B. What's the matter? C. Is this your bag? D. What colour are your shoes? E. Sorry, I don't know. F. I found it on the school bus.

A: , Sam?

B: I lost my bag.

A:

B: My new shoes and my cap are in it.

A: What colour is your cap?

B: It's yellow.

A:

B: They are green.

A: Look!

B: Yes, it is. Where did you find it?

A:

B: Oh! Thank you very much.