am looking for a train . the train should arrive by 18:00 and should go to stevenage .
user
can you provide me with your departure site ?
assistant
i am departing from cambridge on tuesday .
user
there are many options available . is there a certain time you would like to leave ?
assistant
what 1 gets me there before , but closest to 18:00 ?
user
train tr5343 arrives at 16:10 . it is the closest to your required arrival time . would you like to reserve any tickets today ?
assistant
no , i have decided not to book today , thank you , goodbye .