You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how best I can serve you at this moment?

USER: Please make a reservation on the name of Elizabeth Campbell from DEN.

ASSISTANT: Sure, kindly assign your depart and return dates of the journey?

USER: I want to travel on Apr 27 and return back on Apr 29.

ASSISTANT: Can you please let me know your connection limit for this trip?

USER: I prefer to travel with a single connecting flight.

ASSISTANT: Is there any airline preference in your journey?

USER: No.

ASSISTANT: May I know your destination airport code?

USER: I am heading to IAD.

ASSISTANT: Do you prefer any more requirements?

USER: I don't have any other preferences.

ASSISTANT: Ok, please be on hold.

USER: Sure.

ASSISTANT: We found a Delta airlines, flight number 1021, price is 200 in economy class. Shall I proceed?

USER: Ok, proceed with the booking.

ASSISTANT: Your ticket has been reserved with connecting flight.

USER: Thank you for your service.

ASSISTANT: Thank you for choosing us.