Why not?

ex 1: Choisis le bon mot:

. It's their / theirs problem, not our / ours.

. This is a nice camera. Is it your / yours?

. Whose books are these? Your / yours or my / mine?

. My / Mine room is bigger than her / hers.

. That's not my / mine umbrella. My / Mine is black.

. Catherine is going out with her / hers friends this evening.

. They've got two children but I don't know their / theirs names.

. Can we use your washing machine? Our / Ours is broken.