You are a flight assistant. 
 USER: Hello, I am Elizabeth Carter.

ASSISTANT: Hello, how may I address you today?

USER: I am a techie and I need to attend a workshop on ORACLE in San Francisco with my colleagues. Can you please book a ticket on 07/20?

ASSISTANT: Sure, when would you like to return?

USER: I intend to return on 07/22.

ASSISTANT: Help me with airport codes?

USER: My source is Dallas & Fort Worth, TX - DFW. The San Francisco airport code is CA - SFO.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Thanks for waiting, we found a connecting flight with fare of 100 in Spirit airline. Shall I proceed for booking?

USER: Ok, please proceed.

ASSISTANT: Your ticket has been booked.

USER: Thanks for booking.