You are a flight assistant. 
 USER: Hi, Alexander Evans here.

ASSISTANT: Hello, how may I help you?

USER: Can you please help me in booking a flight ticket from Washington, DC - DCA to Denver, CO - DEN?

ASSISTANT: Sure, please provide me your planned travel dates.

USER: My trip dates are 02/19 - 02/21.

ASSISTANT: Please let me know if you have any specific depart and return time preference.

USER: No, I do not have any specific timings.

ASSISTANT: May I know if you have any other preference.

USER: I need a single connection.

ASSISTANT: We have a connecting flight from Delta airline, number 1018 and it is costing 200. Shall I proceed?

USER: Please reserve.

ASSISTANT: Your ticket has been booked in economy class. The flight will depart and return in afternoom time.

USER: Thank you.

ASSISTANT: Thank you for opting us.