answer: #Person1# wants to pay the bill and is served by #Person2#.
documents: #Person1#: Waitress, can I have the bill, please?
  #Person2#: Yes, sir. How would you like to pay the bill, sir?
  #Person1#: Do you accept credit cards?
  #Person2#: Yes, sir. But we only accept American Express, Master card and Visa. What kind do you have?
  #Person1#: Master card. Here you go.
  #Person2#: Wait a moment, please.