You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Dennis Wright here.

ASSISTANT: Wright, how can I aid you today?

USER: I'm planning to visit Washington, can you please book a ticket from SEA to IAD?

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

USER: Sure, my planned departure and return travel dates are 14th and 16th of March.

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

USER: Sure, please check for economy class ticket.

ASSISTANT: I found a flight for you with UA airline and it costs you 100 in economy class. Shall I proceed?

USER: That's fine, you can proceed for booking the ticket.

ASSISTANT: Your ticket has been booked with 1000 flight number.

USER: Thank you so much for your help in booking the ticket.

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