You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Katherine Nelson here.

ASSISTANT: Nice to meet you Katherine.

USER: Can you please reserve me a flight from DCA to reach IAH?

ASSISTANT: Sure, tell me your travel dates please?

USER: My planned travel dates are Mar 20th and Mar 22nd.

ASSISTANT: Ok, please wait.

USER: I need a single connecting flight.

ASSISTANT: Sure.

USER: Make sure that, my depart must be in the evening.

ASSISTANT: Thanks for your patience. I have found united airlines which flies with one connection . It is in economy class and the fare is only 200.

USER: Please, recheck whether it departs in the evening or not.

ASSISTANT: Yes, it is in the evening..

USER: Ok, please proceed by booking.

ASSISTANT: Yes, I have confirmed your flight ticket with flight number 1010.

USER: Thank you.

ASSISTANT: Thank you.