You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: I am Jack Clark, please search flights on these dates 07/25 and 07/27, to attend my semester exams, so can you help me for this?

ASSISTANT: Sure, could you please provide your codes of airport you want to travel?

USER: I would like to travel from DCA to DEN.

ASSISTANT: Ok, please wait for a while.

USER: Ok, I will wait for your reply, but get back with best airline.

ASSISTANT: Ok, there is a flight 1023 in UA airline matching your dates with price 100. Shall I proceed?

USER: Yes, proceed.

ASSISTANT: Ok, your booking is done.

USER: Thank you for confirming my flight ticket.

ASSISTANT: You are welcome, have a nice journey.