The person in the house next to mine knows someone _________ met the Queen

Did you meet the lady ______ uncle works in the library? 

The police want to find out ______  drove the red car into the shop window.

I think you will see that this is the best museum _____  you can find in the town. 

There is a new television programme called: ______ wants to be a millionaire? 

I'm looking at the photograph _______ you sent me with your letter.