who which where

... is calling?

... should I go?

... dish should I choose?

... is the library?

... is the best football player in the world?

... day do you prefer for meeting - today or tomorrow?

... is that boy?

The dog ... you saw outside is my neighbour’s.

This is the house ... my son lives.

The woman ... called yesterday wants to buy the house.

Did you see the letter ... came today?

The gym ... I do an exercise class is going to close.