You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: Please book a flight ticket from DEN to LAS to attend a music concert.

ASSISTANT: Ok, can you please provide your travelling dates?

USER: I want to take off on Dec, 6 and return back on Dec, 8.

ASSISTANT: Ok, do you have any specifications?

USER: I would prefer to connecting flight.

ASSISTANT: Ok, hold on for a moment. Let me check the best available flight for you.

USER: Sure.

ASSISTANT: I found a flight for you with United Airlines and it costs you 200. Shall I proceed?

USER: Please proceed.

ASSISTANT: On whose name you would like to book this ticket?

USER: John Nelson here.

ASSISTANT: Your ticket has been booked with 1023 flight number.

USER: Thank you.