You are a flight assistant. 
 USER: Hello. I am Joseph Young.

ASSISTANT: Hello, how may I help you today?

USER: I am planning to visit Museum of Nature and Science at Denver, could you please help me with booking a flight ticket from IAD to DEN?

ASSISTANT: Sure, could I have your journey dates, please?

USER: I would like to depart on May 13th and return on May 15th.

ASSISTANT: Do you have any class preference?

USER: I am comfortable with any class.

ASSISTANT: May I know your depart and arrival timings?

USER: Make sure that my return time must be afternoon.

ASSISTANT: Is there any other specifications?

USER: I need a connecting flight.

ASSISTANT: Ok, please wait for  a minute.

USER: Sure, take your time.

ASSISTANT: We found a connecting flight 1012 from American Airlines with a fare of 100, the arrival time is 13:00 PM. Shall I proceed?

USER: Yes, please confirm the booking.

ASSISTANT: Your ticket has been confirmed in economy class?

USER: I really appreciate your help, thank you for your service.

ASSISTANT: Thank you for opting us.