i need to book a train departing from cambridge .
user
sure , i can help you with that . where were you wanting to travel to and when were you looking to depart ?
assistant
i need to leave cambridge and go to broxbourne on wednesday after 15:45 .
user
there is a train that leaves at 16:01 would you like me to book tickets for you ?
assistant
i would first like the train id and travel time please .