i want a train that leaves on monday .
user
there are several trains leaving on monday . may i have your destination ?
assistant
i would like to travel from norwich to cambridge . are there any leaving after 21:00 ?
user
yes , i could get you tickets on a train leaving at 21:16 . tr8920 . would you like to book passage ?
assistant
can you tell me what the arrival time is ?
user
it should arrive by 22:35
assistant
would yopu like me to book it for you ?