You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Mark Hall.

ASSISTANT: How can I aid you?

USER: Can you please book a flight ticket from LGA to ORD? As I have to go Chicago to give presentation.

ASSISTANT: Sure, may I know your travel dates please?

USER: Thank you. I have planned my travel dates as Aug 05 and Aug 07.

ASSISTANT: Do you have any connection limit?

USER: I am looking for single connecting flight but direct flight is also fine with me.

ASSISTANT: May I know about your class preference?

USER: Sure, actually I don't have any specific class to travel.

ASSISTANT: Do you have any other specifications?

USER: Yes, I would like to return in the afternoon time only.

ASSISTANT: Ok, please wait for a while.

USER: Sure, take your time.

ASSISTANT: Sorry, no flights are running on your routes.

USER: Oh! It is sad to hear. Anyway, thank you for your time.

ASSISTANT: Thank you for reaching us.

USER: Most welcome.