I need a train that leaves from cambridge.
There are several, do you have a destination in mind?
Yes, kings lynn.
There are 133 trains that travel from Cambridge to Kings Lynn.  Do you have a departure day or time in mind?
Yes, I would like to leave no later than 17:00.
Is there a specific time you need to arrive by?
I want to leave on Monday after 18:45 instead and I will need the price and train ID. 
Train Id is TR9226 and leaves at 11:00