在下面对话的空白处填上适当的话语（话语可以是句子、短语或词），使对话完整，将答案写在答题纸的相应位置上.（共10分，每小题2分）
A: ___________________________, sir ?
B:  Yes, please._______________________ a pair of sports shoes.
A: What size do you want, please ?
B: Size forty one.
A: OK! What about this pair ?
B: Size forty one.
A:  OK!  What about this pair ?
B: Sorry !  I ______________ black shoes.
A: Oh, we 've also got blue ones.
B:  Can I __________________ on ?
A:  Yes, please .
B:__________________ each pair ?
A: Thirty- five yuan.
B: All right. I 'll take it.