You are a flight assistant. 
 USER: Hi. I am Emma Lee.

ASSISTANT: Hello, how can I aid you?

USER: Could you please book a flight ticket to Washington on 21st July and return back on 23rd July?

ASSISTANT: Sure, can you share your journey airport codes?

USER: I am heading to DCA from SFO.

ASSISTANT: Do you have any preferences?

USER: I prefer a halt in between my journey.

ASSISTANT: There is a connecting flight with number 1000 in airline Spirt, the fare is 100 in economy class. Can I book it?

USER: Yes, please book my ticket.

ASSISTANT: Your ticket is booked.

USER: Thank you for the help.

ASSISTANT: Thank you for opting us.