You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I want to book a flight from IAD to OAK. Can you book a flight for me?

ASSISTANT: Sure, when are you planning to start and return on?

USER: I will fly on July 18 and return on July 20.

ASSISTANT:  Do you have any class preference?

USER: I prefer a connecting flight.

ASSISTANT: Is there any another specifications on your trip, so that I can arrange like that only.

USER: No, I do not have any other requirement.

ASSISTANT: Ok, please share your name to proceed further.

USER: My name is Kathleen King.

ASSISTANT: There is a connecting flight-1027, shall I proceed?

USER: Please proceed with booking.

ASSISTANT: Ok, booking is done on AA airlines.

USER: Thank you for helping me.

ASSISTANT: Welcome, have a safe trip.