generate response: I don't have a preferred departure time but the train should arrive by 18:15.. Intent: find_train. Slots: train-arriveby=18:15, train-day=wednesday, train-departure=cambridge, train-destination=norwich, train-leaveat=dontcare
Response: TR1871 arrives by 16:55 and TR6838 arrives by 17:55. They are both the same price. Would you like to book one of these?