单项选择题
A: Would you like a cup of coffee? B:（）
A. That’s Research and Development. B. No， thank you. C. Yes. D. Thank you.
A. that could benefit both of us. B. then he could get a large discount. C. that is made with certain conditions. D. to be more flexible over terms of payment.
A. that could benefit both of us. B. that you have finalized the delivery dates. C. that is made with certain conditions. D. then he could get a large discount.