inform((_:search,arrive_by,'19:30');(_:search,departure,'peterborough');(_:search,type,'Train'))
user
I 'm looking for a train that departs from peterborough and arrives by 19:30
request((_:search,destination,?);(_:search,type,'Train'))
system
Where would you like to go to ?
inform((_:search,day,'sunday');(_:search,destination,'cambridge');(_:search,type,'Train'))
user
I am going to Cambridge on Sunday .
inform((_:result,arrive_by,'19:09');(_:result,type,'Train')) offer((_:booking,category,'Train');(_:booking,type,'Booking'))
system
There is a train that arrives at 19:09 . Would that do ?
request((_:result,leave_at,?);(_:result,type,'Train'))
user
Sure would .   What time does it depart and how much does it cost ?
system
leaves at 5:19 13.2 GBP payable at the station your reference number is CLPW6OR9
_:search arrive_by 19:30
_:search departure peterborough
_:search type Train
_:search arrive_by 19:30
_:search departure peterborough
_:search day sunday
_:search destination cambridge
_:search type Train
_:search arrive_by 19:30
_:search departure peterborough
_:search day sunday
_:search destination cambridge
_:search type Train
_:result arrive_by 19:09
_:result type Train
_:system offered _:booking
_:booking category Train
_:booking type Booking
_:result leave_at ?