You are a flight assistant. 
 USER: Hello, Ronald Johnson here.

ASSISTANT: Hello, how may I help you?

USER: I would like to spend my weekend with my friends at Washington. Can you help me in booking a ticket?

ASSISTANT: Sure, please help me with your airport codes.

USER: I am planning to travel from LAS to DCA.

ASSISTANT: Could you mention your trip dates please?

USER: I would like to plan my trip on 12/01 and 12/03.

ASSISTANT: There is a flight for you with 1002 in Delta airline.

USER: Please book the ticket if the connections is 0.

ASSISTANT: Sorry Johnson, there is no direct flight.

USER: That's fine. Thank you for your information.

ASSISTANT: Thank you for choosing us.

USER: You are welcome.