You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I'm doing a documentary on some plant species, as a part of that I need to visit Denver botanical gardens. Please book a ticket from OAK to DEN.

ASSISTANT: Sure, will you mention your travelling dates please?

USER: Sure, I would like to depart from my location on 18th September and I want to return back by 20th September.

ASSISTANT: Do you have any preferences about flight connections?

USER: Usually, I prefer single connected flight. Search for the flights according to that.

ASSISTANT: Do you have any preferences about class?

USER: No, I don't have any other specifications actually.

ASSISTANT: Please mention your name.

USER: Well, myself Debra Brown.

ASSISTANT: The American airlines providing an economy class flight with price 100 and the connections 1. Shall I confirm your ticket?

USER: That's perfectly matching my requirements, proceed for booking the ticket.

ASSISTANT: Your ticket is booked. The flight number is 1010.

USER: Thank you for your help.

ASSISTANT: Welcome, have a great day.