You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I would like to book a ticket from DCA to BOS, can you please help me out?

ASSISTANT: Sure, when are you willing to travel?

USER: I am travelling on these dates July 27th and 29th.

ASSISTANT: May I know your name please?

USER: Larry Wright here.

ASSISTANT: Do you have any preferences?

USER: I prefer normal-cost.

ASSISTANT: We found a flight in an airline United with 1000 number having a single connection in an economy class. Shall I proceed to book?

USER: Ok, you can proceed.

ASSISTANT: Your flight ticket has been booked.

USER: Thank you for your services.

ASSISTANT: Thank you for reaching us.