You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: Sarah Walker here. I would like to visit SFO to DEN, can you help me to book a flight ticket?

ASSISTANT: Ok, may I know your trip dates?

USER: My planning dates are 04/12 and 04/14.

ASSISTANT: Wait for a while.

USER: Sure.

ASSISTANT: AA airlines providing service to you with the price 200, shall I book it?

USER: Proceed with that booking.

ASSISTANT: Ok, your ticket has been done.

USER: Thanks for helping me.

ASSISTANT: Thanks for choosing us, have a good day.