You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you today?

USER: Could you please book a flight ticket from DEN to BOS?

ASSISTANT: Sure, may I know your trip dates?

USER: My trip dates are Jan 01 and Jan 03.

ASSISTANT: Do you have any specifications?

USER: I need a direct flight. And I want to return in the evening.

ASSISTANT: May I know your good name?

USER: I am Thomas Brown.

ASSISTANT: I found a flight with the price of 100 having direct flight and return at 21:00 hours. Can I proceed to booking?

USER: Ok, proceed.

ASSISTANT: Your ticket has been reserved with the flight- 1021.

USER: Thank you.

ASSISTANT: Thank you for reaching us.