1. I went to see her flat, which shelived in when she was a
student (non-identifying clause).
2. I went to see the flat which/thatshe lived in when she
was a student (identifying clause).
3. Come and meet the friends who/that Itold you about
(identifying clause).
4. Come and meet my friends, most of whomyou know
(non-identifying clause).
5. This is the Director, whofounded the company (nonidentifying
clause).
6. There are several directors. This is the director who/that
founded the company ( identifying clause).
7. What we really need is a dam that/whichwill be big
enough to supply the whole area with water (identifying clause').
8. I have a photo of the Kariba dam, whichsupplies the
whole area with power (non-identifying clause).
9. I’d like to introduce Mr. Bridge, who/thatI used to work
with (non-identifying clause).
10. Can that be the Mr. Bridge whomI used to work with?
(identifying clause).
11.I have to study mathematics, whichI do not enjoy (nonidentifying
clause).