1-Defining relative clauses with who, that and which :
I spoke to the woman who owns the hotel.
Did you see the letter that came this morning?
1-These clauses tell us which person or thing the speaker means (for example who owns the hotel tells us which woman ; and that came this morning tells us which letter).
2-We use who for people .
I spoke to the woman. She owns the hotel.
I spoke to the woman who owns the hotel.
The man was very nice. He interviewed me.
The man who interviewed me was very nice.
3-We use that for things.
Did you see the letter? It came this morning.
Did you the letter that came this morning?
The keys have disappeared. They were on this table.
The keys that were on this table have disappered.
4-We can use which instead of that (to talk about things) in a defining relative clause.
Did you see the letter which came this morning?
The keys which were on this table have disappeared.
In an informal style , it is also possible to use that instead of who (to talk about people).
I spoke to the woman that owns the hotel.
2- Leaving out who, that and which in defining relative clauses:
1-Who, that and which can be the subject of a defining relative clause.
Marianne is the girl who invited us to the party. (who = subject : she invited us to the party).
Marianne is the girl who we met last night. (who = object : we met her last night).
2-We often leave out who , that or which when they are the objects in defining relative clauses.
Marianne is the girl we met last night. (we met her last night).
Have you seen the book I put on this table? (I put it on this table).
3-But we cannot leave out who , that or which when they are the subjects in these clauses.
Marriane is the girl who invited us to the party. (Not : Marianne is the girl invited usto the party.)
Have you seen the book that was on this table? (Not : Have you seen the book was on this table?)
4-We can use whom instead of who (for people) when it is the object of the verb in a relative clause.
I met a woman whom I know. (I know her)
But whom is quite formal and not very common in everyday speech. Instead , we use who or that (or we leave them out).
3-Defining relative clauses with whose, where, when and why/ that:
1-Whose: We use whose in relative clauses (in place of his, her, their, etc.) to talk about possesion.
I have got a friend. His brother is an actor.
I have got a friend whose brther is an actor.
They are the people. Their house caught fire.
They are the people whose house caught fire.
2-where , when and why/that:
A- We can use where (for places) and when (for times) in relative clauses.
The factory where I work is going to close down.
Is there a time when we can meet?
B- After the reason we can use why or that in relative clauses.
Is there a reason why/that you want to leave now?
C- We can leave out when , why and that. We can also leave out where if we use a proposition.
Is there a time we can meet?
Is there a reason you want to leave now?
The hotel we stayed at was very small.
4-Defining and non-defining relative clauses:
1- ‘Defining’ relative clauses identify nouns: these clauses tell us which person , thing , etc the speaker means.
I spoke to the woman who owns the hotel. (who owns the hotel tells us which woman)
The house which Sue has bought is over 100 years old. (which Sue has bought tells us which house)
2- ‘Non-defining’ relative clauses do not tell us which person , thing , etc the speaker means ; these give more information about a person or thing already identified.
Ken’s mother , who is 69 , has just passed her driving test. (who is 69 does not tell us which woman ; we already know that is Ken’s mother.)
Non-defining clauses are more common in a formal style , especially in writing. When we write these clauses , we put commas (,) at the beginning of the clause. (and often at the end of the clause).
Last weekend I met Sue , who told me she was going on holiday soon.
Frank Morris , who is one of my best friends , has decided to go and live in France.
3- In a non-defining clause we always use who for people and which for things ; we cannot use that.
She gave me the key , which I put in my pocket.
In a non-defining clause we cannot leave out who or which.
5-Non-defining relative clauses with whose , where , when and whom:
We can use whose , where and when in non-defining relative clauses. We can also use whom instead of who when it is the object of the verb in a non-defining clause.
Tina Harris , whose brother is the actor Paul Harris , is a good friend of mine.
We visited a town called Chrischurch , where we had lunch in an Italian restaurant.
We’re going on holiday in September , when the weather isn’t so hot.
Sarah Ross, who/whom you met in Madrid last summer, will be at the party tonight.
6-Relative clauses with prepositions + which and whom :
We can use a preposition before which and whom eg in which , with whom in a defining relative clause.
That’s the town in which he was born.
The people with whom I stayed were very kind.
But , in everyday speech , it is more usual to put the preposition at the end of the clause and to leave out the pronoun which , whom , etc.
That’s the town he was born in.
The people I stayed with were very kind.
A-In a formal style, we can also use a preposition before which and whom in a non-defining relative clause.
She’s studying chemistry , which I know very little about.
Mr and Mrs Morris , who we went on holiday with live in Bristol.
Note that we cannot leave out the pronoun which , who , etc in a non-defining clause.
B-Note the structure some of/many of/none of/all of/etc + which / whom.
A number of my friends , some of whom you’ve met before, will be at the party.
He gave me a lot of advice , much of which was very useful.
7-Which referring to a whole clause:
We can use which to refer back to a whole clause. Compare:
He offered to help me. This was very kind of him.
He offered to help me , which was very kind of him.
which = the fact that he offered to help me