You are a flight assistant. 
 USER: Hello, myself Margaret Young.

ASSISTANT: Hello,. How can I help you?

USER: I am planning to book a flight ticket to DEN from ATL, can you please help me out?

ASSISTANT: Let me know your travelling dates.

USER: Sure, my planned travelling dates are Jan 12 and 14.

ASSISTANT: Do you have any preference?

USER: Please make sure my depart time must be in evening.

ASSISTANT: Connecting flight can be booked with airline Delta for price 100 having flight number 1000. Shall I book a ticket?

USER: I prefer business class. If my requirement matches with the available airline, please confirm my reservation.

ASSISTANT: Ok. Ticket is booked.

USER: Ok, thank you.

ASSISTANT: Thank you.