What is a Relative Pronouns?
A relative pronoun introduces a relative clause — a subordinate clause that gives more information about a noun in the main sentence. The pronoun connects the clause to the noun it modifies and acts as the subject or object within that clause.
English has five core relative pronouns: <strong>who</strong> (for people), <strong>which</strong> (for things and animals), <strong>that</strong> (for people or things in defining clauses), <strong>whose</strong> (for possession), and <strong>where</strong> (for places). Choosing the right one depends on two questions: What kind of noun are we referring to? And is the clause defining or non-defining?
This page focuses on relative pronouns in defining relative clauses — clauses that are essential to the meaning of the sentence. For non-defining relative clauses (where the pronoun choice is more restricted), see the separate guide.
Relative Pronoun Quick Reference
The relative pronoun immediately follows the noun it refers to and introduces the relative clause. The clause can come in the middle or at the end of the main sentence.
Noun + relative pronoun + rest of relative clausePronoun reference table
| Pronoun | Refers to | Used in | Example |
|---|---|---|---|
| who | people | defining & non-defining | The woman who called you is here. |
| which | things, animals | defining & non-defining | The book which I recommended is sold out. |
| that | people or things | defining only | The film that won the award was excellent. |
| whose | possession (people, things) | defining & non-defining | The student whose essay I read was talented. |
| where | places | defining & non-defining | The city where I grew up has changed a lot. |
When to Use Relative Pronouns
Who — for people
We use who when the relative clause refers to a person or people. It can act as the subject or the object of the relative clause. Who works in both defining and non-defining relative clauses.
- The doctor who treated me was very professional. (who = subject)
- The colleague who I mentioned has just been promoted. (who = object)
- The students who passed the exam were very relieved.
Which — for things and animals
We use which when the relative clause refers to a thing, object, concept, or animal. Like who, it can be the subject or object of the clause and works in both defining and non-defining contexts.
- The report which was published last week attracted a lot of attention. (which = subject)
- The laptop which I bought last year has already broken down. (which = object)
- She adopted the cat which had been living in the garden for months.
That — for people or things in defining clauses
That can replace both who and which in defining relative clauses. It is very common in spoken English and informal writing. However, that cannot be used in non-defining relative clauses — those require who or which.
- The woman that runs the café is my neighbour. (replaces who)
- The film that won the award was made on a tiny budget. (replaces which)
- Everything that he said turned out to be true.
Whose — for possession
We use whose to show that something belongs to the person, animal, or thing referred to by the main noun. It replaces a possessive determiner (his, her, its, their) and is used for both people and things.
- The author whose novel I read last summer has just won a major prize.
- A company whose reputation is built on trust does not cut corners.
- I know a mechanic whose prices are very reasonable.
Omitting the relative pronoun (contact clause)
When the relative pronoun is the object of the relative clause — and the clause is defining — the pronoun can be left out entirely. This is called a contact clause and is very common in spoken English. You can never omit a subject relative pronoun.
- The book (that) I recommended is in the library. (that = object — can omit)
- The person (who) you spoke to is the manager. (who = object — can omit)
- The film that won the award was excellent. (that = subject — cannot omit)
Relative Pronouns at a Glance
That vs Which
In defining relative clauses, that and which are often interchangeable when referring to things. But there are contexts where one is clearly preferred over the other.
that — preferred after superlatives and "all / everything"
This is the best cake that I have ever eaten.
After superlatives (best, worst, most interesting) and after all, everything, nothing, the only — that is more natural than which.
which — used in non-defining clauses
The cake, which my aunt made, was absolutely delicious.
In non-defining relative clauses (with commas), only which is correct. That cannot be used here. The clause adds extra, non-essential information.
that — preferred in spoken / informal English
The film that everyone is talking about is finally available.
In everyday conversation and informal writing, that is very common for both people and things. Which sounds slightly more formal.
which — required after a preposition
The tool with which he built the shelf was borrowed.
In formal writing, prepositions come before which (never before that). You cannot say "the tool with that he built" — always use which after a preposition.
Who vs That for People
Both who and that can refer to people in defining clauses. The choice is mainly stylistic, but some contexts favour one over the other.
who — more personal, always safe for people
The teacher who helped me most was Mr Garcia.
Who signals clearly that the antecedent is a person. It is the safer, more natural choice in most contexts and is the only option in non-defining clauses.
that — common in informal speech; required in some patterns
The only person that understood the problem was Anna.
After the only, the first, the last, and superlatives referring to people, that is preferred. "The only person who" is also correct, but "that" sounds more natural here.
Common Mistakes
Using "which" for people
✗ The manager which hired me has left the company.
The manager who hired me has left the company.
Which refers to things and animals — never to people. Always use who (or that in defining clauses) when the antecedent is a person.
Using "that" in a non-defining relative clause
✗ My sister, that lives in Madrid, is a doctor.
My sister, who lives in Madrid, is a doctor.
That cannot be used in non-defining relative clauses (those marked by commas). Use who for people and which for things in non-defining clauses.
Repeating a pronoun after the relative pronoun
✗ The book that I read it last week was fascinating.
The book that I read last week was fascinating.
The relative pronoun already replaces the noun — do not add a personal pronoun (it, him, her, them) inside the relative clause to repeat the same reference.
Using "which" instead of "who" after indefinite pronouns for people
✗ Everyone which passed the test received a certificate.
Everyone who passed the test received a certificate.
After indefinite pronouns like everyone, someone, anyone, and nobody that refer to people, use who — not which or what.
Ready to practise?
Put it into practice
Test your understanding with interactive exercises and instant feedback.