UNIT X: STUDY GRAMMAR

 The relative pronouns are:

Relative pronouns used in defining relative clauses:

	Subject	Object	Possessive
For persons	who that	whom/who that	whose
For things	which that	which that	whose/of which

 Defining relative clauses: persons

 Subject: who or that
who is normally used:
The man who robbed you has been arrested.
The girls who serve in the shop are the owner's daughters.
Only those who had booked in advance were allowed in.
Would anyone who saw the accident please get in touch with the police?

But that is a possible alternative after all, everyone, everybody, noone, nobody and those:

Everyone who/that knew him liked him.
Nobody who/that watched the match will ever forget it.

 Object of a verb: whom; who; that
The object form is whom, but this is considered very formal. In spoken English we normally use who or that (that being more usual than who), and it is still more common to omit the object pronoun altogether:
The man (whom/who/that) I saw told me to come back today.
The girls (whom/who/that) he employs are always complaining about their pay.

 With a preposition: whom/that
In formal English the preposition is placed before the relative pronoun, which must then be put into the form whom:
The man to whom I spoke is my cousin. 
In informal speech, however, it is more usual to move the preposition to the end of the clause. whom is often replaced by that, but it is still more common to omit the relative altogether.
The man who/whom I spoke to is my cousin. or The man (that) I spoke to is my cousin.
Similarly:
The man from whom I bought it told me to oil it. or The man (who/that) I bought it from told me to oil it.
The friend with whom I was travelling spoke Spanish. or The friend (who/that) I was travelling with spoke Spanish.
 Possessive:
whose is the only possible form:
People whose rents have been raised can appeal.
The film is about a spy whose wife betrays him.

 Defining relative clauses: things
 Subject:
Either which or that. which is the more formal:
This is the picture which/that caused such a sensation.
The stairs which/that lead to the cellar are rather slippery.
 Object of a verb: which or that, or no relative at all:
The car (which/that) I hired broke down.
which is hardly ever used after all, everything, little, much, none, no and compounds of no, or after superlatives. Instead we use that, or omit the relative altogether, if it is the object of a verb:
All the apples that fall are eaten by the donkey.
This is the best hotel (that) I know.
 Object of a preposition:
 The formal construction is preposition+which, but it is more usual to move the preposition to the end of the clause, using which or that or omitting the relative altogether:
The ladder on which I was standing began to  slip. or The ladder (which/that) I was standing on began to  slip.
 Possessive:
whose+ a clause is possible but with+ a phrase is more usual:
He lived in a house whose walls were made of glass.
He lived in a house with glass walls .
 Relative adverbs: when, where, why
Note that when can replace in/on which (used of time):
the year when (=in which) he was born.
the day when (=on which) they arrived.
where can replace in/at which (used of place):
the hotel where (=in/at which) they were staying.
why can replace for which: The reason why he refused is...
when, where and why used in this way are called relative adverbs.
 Non-defining relative clauses: persons
 Subject: who 
No other pronoun is possible. Note the commas:
My neighbour, who is very pessimistic, says there will be no apples this year.
Peter, who had been driving all day, suggested stopping at the next town.
Clauses such as these are found mainly in written English.
 Object: whom, who
The pronoun cannot be omitted. whom is the correct form, though who is sometimes used in conversation:
Peter, whom everyone suspected, turned out to be innocent.
 Object of a preposition: whom
The pronoun cannot be omitted. The preposition is normally placed before whom:
Mr Jones, for whom I was working, was very generous about overtime payments.
It is however possible to move the preposition to the end of the clause. This is commonly done in converstion, and who then usually takes the place of whom:
Mr Jones, whom I was working for, was very generous about overtime payments.
 Possessive: whose
Ann, whose children are at school all day, is trying to get a job.
This is George, whose class you will be taking.
 Non-defining relative clauses: things
 Subject: which
that is not used here:
That block, which cost £5 million to build, has been empty for years.
The 8.15 train, which is usually very punctual, was late today.
 Object of a preposition:
The preposition comes before which, or (more formally) at the end of the clause:
Ashdown Forest, through which we'll be driving, isn't a forest any longer.
Ashdown Forest, which we'll be driving through, isn't a forest any longer.
His house, for which he paid £10,000, is now worth £50,000.
His house, which he paid £10,000 for, is now worth £50,000.
which with phrasal verbs such as look after, look forward to, put up with... should be treated as a unit, i.e. the preposition/adverb should not be separated from the verb:
This machine, which I have looked after for twenty years, is still working perfectly.
Your inefficiency , which we have put up with far too long, is beginning to annoy our customers.
 Possessive: whose or of which
whose is generally used both for animals and things. of which is possible for things, but unusual except in very formal English:
His house, whose windows were all broken, was a depressing sight.
The car, whose handbrake wasn't very reliable, began to slide backwards.