generate response: Yes, that would work out great. I need to book the trip for four people. Can I get a reference number too please?. Intent: book_train. Slots: train-bookpeople=4, train-day=saturday, train-departure=stevenage, train-destination=cambridge, train-leaveat=09:45
Response: Reference number is : 1QXKJN3D . Is there anything else?