Hi I'm looking for a train for Tuesday. 
Okay what time would you like to depart from Cambridge and arrive in London Kings Cross on Tuesday?
I need to depart after 19:15. Can you please provide me with a price?
The next train departs at 21:00. The price is 23.60 pounds per ticket. Can I book this train for you?
Yes please book this train for me, Thank you.
How many tickets do you need?
I am not ready to book the train yet. Thanks for the help. 
Can I be of further assistance to you today?
No thanks, that is all I needed. 
You're welcome. glad I could help