generate response: yes book it for 4 people. Intent: book_train. Slots: train-bookpeople=4, train-day=thursday, train-departure=cambridge, train-destination=london kings cross, train-leaveat=17:00
Response: Train TR1791 will leave at 17:00 on Thursday. It will cost 94.4GBP. Your reference number is HN91KJWK . Have your luggage ready, thank you!