You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Catherine Parker.

ASSISTANT: How can I provide service to you?

USER: I am shifting from Washington DC - IAD to Las Vegas, NV - LAS. Can you book a ticket for me?

ASSISTANT: Sure, May I know your travelling dates?

USER: Yes, 05/19 an 05/21 are my travel dates.

ASSISTANT: Do you have any other specifications?

USER: Yes, my price range is 1000 with a connection.

ASSISTANT: We have found a flight with direct connection.

USER: Sorry, I prefer only connecting flights.

ASSISTANT: Ok, Thanks for choosing us.

USER: Thanks for your response.