I am looking for a 4 star guesthouse in Cambridge.
I have 18 results that match your request. To help narrow it down, what part of town would you like to stay in? Do you have a price range preference?
The hotel also needs to be cheap and have free wifi.
There are 7 hotels that meet that criteria. Do you have an area preference?
Do any of these 7 have free wifi?
They all have free wifi. 
Any of them will do.  I'll book a room in whichever one you think is best.
The alexander bed and breakfast is in the center of town, would you like help with the booking?
That would be great.  Two nights please.
What day would you be arriving on and for how many people?
Let's try 5 nights, starting Friday, with 2 people. 
I have confirmed your reservation at alexander bed and breakfast starting Friday for 5 nights. Your reference number is K67RS8EB. Is there anything else I can help with?
Yes, I am looking for something to do during my stay. I'd like it to be around the centre area. 
I have many choices: theater, colleges, museums, architecture. Do any of these venues interest you?
Are there any colleges in the centre of town that have free admission?
Yes certainly. We have several. Christ College is a good choice.
That would be fine. Can you confirm the entrance fee?
Christ's College offers free admission.
Fantastic.  I have all of the information I needed, thank you.  Have a great day.
Glad to have been able to assist you. Thank you and have a great day.