根据对话内容，选用方框中适当的句子，补全对话。

A: __1__ 　

B: Yes, please. I want to buy a pair of sports shoes.

A: __2__

B: Size ten or eleven.

A: OK! What about this pair?

B: Sorry! I don't like black. Have you got any other colours?

A: Other colours? __3__

B: Can I have a look at the brown ones?

A: Yes, please.

B: __4__

A: Forty-six yuan.

B: __5__

A: How about forty?

B: No, it's still expensive. What about thirty?

A: Thirty? Er…all right. Please take it.

1．

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2．

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3．

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4．

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5．

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A．It's too expensive. Can it be cheaper?

B．How much does each pair cost?

C．Oh, yes. We've also got blue, brown and white ones.

D．What size do you want, please?

E．Can I help you, sir?

F．May I try them on, please?