generate response: It's a little early in the morning, but it will do, I'll just set my alarm extra loud. Departure time is 06:40?. Intent: find_train. Slots: train-arriveby=07:08, train-day=tuesday, train-departure=cambridge, train-destination=stansted airport, train-leaveat=06:40
Response: Sounds great, I can go ahead and book that. How many tickets will you be needing?