You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Dorothy Evans.

ASSISTANT: How can I aid you?

USER: I have a meeting to attend at Denver, please help me in booking a ticket.

ASSISTANT: Sure, help me with the travelling dates.

USER: My travelling dates are from 10/19 to 10/21.

ASSISTANT: May I know your source and destination?

USER: My source and destination airport codes are LGA and DEN.

ASSISTANT: Give me a minute.

USER: Sure.

ASSISTANT: There is a connecting flight in airline UA. Can I book it?

USER: Ok, please book my ticket.

ASSISTANT: Your ticket is booked in flight number 1011.

USER: Thank you for your help.

ASSISTANT: Thank you for choosing us.