i would like to book a train .
{'service': 'train', 'act': 'request', 'slot_name': 'leave', 'value': '?'} {'service': 'train', 'act': 'request', 'slot_name': 'dest', 'value': '?'} {'service': 'train', 'act': 'request', 'slot_name': 'day', 'value': '?'}
ok , let s narrow this down a bit . where are you traveling to , what day are you traveling , and at what time ?