Relative pronouns
A relative pronoun is a word (who, whom, whose, which, that) that introduces a relative clause, linking it to a noun in the main clause. It replaces a noun already mentioned and adds extra information about it, joining two ideas into one sentence without repeating the noun or starting a new sentence.
Types of relative pronouns
Who / Whom
Refer to people; 'who' is the subject form, 'whom' is the object form (formal).
e.g. The woman who called is my aunt., The man whom I met was kind.
Which
Refers to animals, things or whole ideas, usually in non-defining or defining clauses.
e.g. The car which broke down is old., She passed, which surprised everyone.
That
Refers to people, animals or things; used mainly in defining (essential) clauses and often in informal speech.
e.g. This is the book that I borrowed., He is the boy that won the prize.
Whose
Shows possession, linking a noun to something belonging to a person, animal or thing.
e.g. The student whose essay won is here., A house whose roof leaks needs repair.
Where / When / Why (relative adverbs)
Not technically pronouns but often grouped with relatives; they replace phrases like 'in which' or 'for which'.
e.g. The town where I grew up is small., I remember the day when we met.
Rules to remember
- Use 'who' or 'whom' for people, 'which' for things or animals, and 'that' for people or things in defining clauses.
- Defining (essential) relative clauses give necessary information and use no commas; non-defining clauses add extra information and require commas.
- 'That' cannot be used in non-defining clauses; use 'who' or 'which' instead after a comma.
- 'Whose' shows possession and works for people, animals and things alike.
- The relative pronoun can often be omitted when it is the object of the clause, e.g. 'the book (that) I read'.
Examples in sentences
| Example | How it works |
|---|---|
| The teacher who explained the essay structure was very helpful. | 'Who' introduces a defining clause about a person. |
| My laptop, which I bought last year, has already broken. | 'Which' introduces a non-defining clause set off by commas. |
| This is the report that the manager approved yesterday. | 'That' introduces a defining clause; commas are not used. |
| The scientist whose research won the award studies climate change. | 'Whose' shows possession linking the scientist to the research. |
| I finally visited the museum where the exhibition was held. | 'Where' functions as a relative adverb meaning 'in which'. |
| The candidate to whom the letter was addressed did not reply. | 'Whom' is used formally as the object after a preposition. |
| The book (that) she recommended changed my perspective. | The object relative pronoun 'that' can be omitted. |
Common mistakes
Incorrect: The man which called was my brother.
Correct: The man who called was my brother.
Incorrect: My car, that is new, broke down yesterday.
Correct: My car, which is new, broke down yesterday.
Incorrect: She is the person whom lives next door.
Correct: She is the person who lives next door.
Why this matters for IELTS
Using relative pronouns correctly lets you combine short sentences into longer, more sophisticated ones, which directly boosts your Grammatical Range and Accuracy score in Writing and Speaking. Examiners reward candidates who use defining and non-defining clauses accurately and vary their relative pronouns (who, which, whose) rather than overusing 'that'. Just make sure comma placement and pronoun choice match the clause type, since errors here are common and noticeable.
Frequently asked questions
What is a relative pronoun in simple terms?
It is a word like who, which, whose or that which connects extra information about a noun to the main sentence, avoiding repetition of that noun.
What is the difference between 'who' and 'whom'?
'Who' is the subject form used when the pronoun performs the action, while 'whom' is the object form used when the pronoun receives the action, often after a preposition.
Can 'that' replace 'who' or 'which'?
Yes, in defining clauses 'that' can replace 'who' or 'which', but it cannot be used in non-defining clauses that are separated by commas.
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