generate response: Yes, can I book the 20:40 train for three people?. Intent: book_train. Slots: train-bookpeople=3, train-day=friday, train-departure=cambridge, train-destination=stansted airport, train-leaveat=20:40
Response: Booking was successful, your reference number is N9PDDWD8 . You pay at the station 30.29 GBP.