Assistant:Can I help you?
Customer: Yes,I'm looking for a blue jumper.
Assistant:What size are you?(e.g. large? small? medium? 14? 16?)
Customer:Where's the changing room?
Assistant: It's down there on the right.
Customer:Yes, I'll take this one.Excuse me. Where will l pay for these?
Assistant:Over at the cash desk.
Customer:And can I pay by credit card?
Assistant:you are welcome!