generate response: I need to leave Cambridge after 21:15. Intent: find_train. Slots: train-day=monday, train-departure=cambridge, train-destination=broxbourne, train-leaveat=21:15
Response: There are two trains you can take on Monday, either the 22:01 (arrive 23:01) or the 23:01 (arrive 24:01). Which train do you prefer?