You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello. How can I render you today?

USER: Please book a ticket from DCA to LAS.

ASSISTANT: Sure, I am here to help you. May I know your travel dates please?

USER: Departure is by 11/16 and 11/18 is return date.

ASSISTANT: Ok, hold on for a moment. Let me check the best flight for you.

USER: Sure.

ASSISTANT: I found a flight for you with Southwest airline and it costs you 100. Shall I proceed to reserve a seat in this particular airline?

USER: Is it a connecting flight.

ASSISTANT: Yes, it is having a single halt. Shall I proceed?

USER: Please book a flight.

ASSISTANT: On whose name you would like to book this ticket?

USER: I am Catherine Clark.

ASSISTANT: Your ticket has been booked with 1003 flight number Clark.

USER: Thanks.

ASSISTANT: Welcome, thank you for choosing us. Have a safe flight.