I would like to visit a college in the centre please.
There are 5 colleges in the centre. Christ's college is free, would you like more information on that?  
Yes. I would like information on the other 4 colleges too.
Corpus Christi is at King's Parade and costs 2 pounds.  The other 3 are free.  Would you like their addresses?
No the Corpus Christi will do, could you just give me the postcode for that also?
The postcode for Corpus Christi is cb21rh.  Is there anything else I could help you with today?
I also need a train going to Stansted.
i have found 133 entries. could you be more specific so we can narrow it down? what day are you traveling?
Sorry.  I want to leave Cambridge on Sunday after 8:30.
Train TR8500 leaves Cambridge at 08:40 and will arrive at the airport by 09:08. Would that work for your schedule? 
What is the price?
It's 8.08 pounds per ticket. Would you like me to book it for you?
No, that will be all for today. Thank you for your help!
Okay great, have a nice day!