1. RELATIVE CLAUSES: 1) DEFINING 2) NON-DEFINING

2. DEFINING RELATIVE CLAUSES (DR)
SHE LIKES PEOPLE WHO ALWAYS TELL THE TRUTH

3. NON-DEFINING RELATIVE CLAUSES (NDR)
MY FRIEND ANDREW, WHO IS SCOTTISH, PLAYS THE BAGPIPES

4. DR CLAUSES MORE COMMON IN SPOKEN LANGUAGE

5. NDR CLAUSES MORE COMMON IN WRITTEN LANGUAGE

6. DR CLAUSES POSSIBLE PRONOUNS person thing
Subject WHO / THAT THAT / WHICH
Object / THAT / THAT
RELATIVE PRONOUN: OBJECT
Did you like the present (that) I gave you?
RELATIVE PRONOUN: SUBJECT
I met a man who works in marketing

7. NDR CLAUSES POSSIBLE PRONOUNS person thing Subject WHO WHICH
Object WHO / WHOM WHICH
RELATIVE PRONOUN CANNOT BE LEFT OUT

8. Fill in the gaps with a relative pronoun
The new terminal, ______ will be finished by May, has been designed by a famous architect
Have you finished the book ______ I lent you?
The Prime Minister, ______ the paparazzi follow everywhere, has a new girlfriend
I don’t know the man ______ arrived just after you

9. PREPOSITIONS: DR AND NDR
Prepositions come at the end in most cases
I can always rely on my friend 
She’s a friend I can always rely on
I went to school with Mary 
This is Mary, who I went to school with
Prepositions come before the pronoun in a formal written style
She is a friend on whom I can rely
It is a fact with which you cannot argue

10. OTHER RELATIVE PRONOUNS
WHICH
WHOSE
WHAT
WHY
WHEN
WHERE

11. WHICH
Can be used in NDR clauses to refer to the whole of the sentence before
She arrived on time, which amazed everybody
They had everything ready for us, which was nice

12. WHOSE Can be used in both DR and NDR clauses
That’s the woman whose son ran over my dog
My parents, whose only interest is gardening, never go away on holiday

13. WHAT Is used in DR clauses to mean the thing that
Has she told you what’s worrying her?
What you need is love

14. WHY Can be used in DR clauses to mean the reason why
I don’t know why we are arguing

15. WHEN, WHERE Can be used in DR and NDR clauses
Tell me when you expect to arrive
We’ll go on Monday, when I’m free
The hotel where we stayed was excellent
He works in Oxford, where my sister lives

16. AND FINALLY...

17. REDUCED RELATIVE CLAUSES
When a DR clause has a continuous or passive verb form, we can leave out who, that, which and the auxiliary
Everyone (who is) living in the area complains about the noise
The first novel (that was) written by Doris Lessing is The Grass Is Singing