generate response: I need to leave after 17:45 on tuesday. Intent: find_train. Slots: train-day=tuesday, train-departure=cambridge, train-destination=london kings cross, train-leaveat=17:45
Response: There are 3 trains that match your request. They leave at 19:00, 21:00, and 23:00 respectively. Would you like to buy a ticket for one of these?