I need a train to Stevenage.
Absolutely. From where would you like to depart?
I am leaving out of Cambridge. I need the ticket for Sunday. 
TR5390 is the first train of the day leaving at 5:21 would that work for you?
Unfortunately I need to leave after 09:30, is there one available then?
Sure thing, train TR8464 leaves at 11:21. Will that work? 
That will probably work fine.  Can you tell me the travel time for that train?
The first train of Sunday leaves at 11:21 and arrives by 12:10. Does that meet your requirements?
By travel time, I mean the duration of the train trip.
I'm sorry.  That comes out to a 49-minute train ride.  Does that sound agreeable to you?
Yes that will be fine.
Am I booking one ticket?
No, that's not necessary. I can book it later. Thanks. Have a good day. 
Thank you for using our system!
Thanks again. Goodbye!
Thank you! Goodbye.