Relative Clauses (Defining)
Use who/that for people, which/that for things, whose for possession, and where for places to add essential identifying information right after the noun — never with a comma — and drop the pronoun only when it is the object of its own clause, never when it is the subject.
Formula
Examples
Usage
- •Identifying exactly which person, thing, or place you mean out of a group
- •Giving essential information that can't be removed without changing the meaning
- •Joining two short sentences about the same noun into one clear sentence
- •Showing possession (whose) or location (where) within the description
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Try 5 cards free — no signup →Who, which, or that — which relative pronoun do I use?
Use who for people ("the man who called you"), which for things ("the keys which were on the desk"), and that for either, especially in everyday speech ("the book that I read"). Use whose for possession, regardless of whether the owner is a person, animal, or thing ("the girl whose dog won"), and where for places ("the house where I grew up").
Can I drop the relative pronoun?
Only when it's the object of its own clause: "The film (that) we watched was boring" — "that" can be dropped because "we" is the subject of "watched." You can never drop a subject relative pronoun: "The man who called you" cannot become "The man called you" without changing the meaning entirely — the pronoun is doing essential grammatical work as the subject.
Do defining relative clauses need commas?
No — a defining (identifying) relative clause supplies information the sentence needs to make sense, so it's never set off by commas. Adding a comma shifts the meaning toward non-defining and can quietly change what the sentence claims: "the students who passed celebrated" (only the ones who passed) vs "the students, who passed, celebrated" (all of them, and by the way, they all passed).
Comparison Table
| Form | Refers to | Role | Example |
|---|---|---|---|
| who | People | Subject or object | The man who called you is my brother. |
| which | Things | Subject or object | I lost the keys which were on the desk. |
| that | People or things | Subject or object (informal default) | The film (that) we watched was boring. |
| whose | Possession (any owner) | Determiner | She's the girl whose dog won. |
| where | Places | Adverbial | This is the house where I grew up. |
Save this comparison chart
More Examples
The man who called you is my brother.
Subject relative clause with who (people)
I lost the keys that were on the desk.
Subject relative clause with that (things)
This is the house where I grew up.
Relative clause of place with where
She's the girl whose dog won the competition.
Possessive relative clause with whose
The film (that) we watched last night was boring.
Object relative clause — pronoun can be omitted
The people (who) I met at the party were really friendly.
Object relative clause with who — pronoun optional, especially in speech
Common Mistakes
- ✗Doubling the subject with a personal pronoun: "The man who he called me" instead of "The man who called me."
- ✗Mixing up who/which: "The book who I read" or "The man which I met" — who is for people, which/that is for things.
- ✗Adding a comma as if the clause were non-defining, when it's essential to identifying the noun: no comma before defining who/which/that/where/whose.
- ✗Dropping the relative pronoun when it's the subject of its clause: "The man lives next door called me" is wrong — subject who/that/which must stay.
Tips
- ✓Ask: is the relative pronoun the subject or object of its own clause? Subject pronouns (who/which/that) can never be dropped; object pronouns can.
- ✓In everyday spoken English, "that" is often preferred over "who"/"which" — especially after superlatives and words like all, everything, the only.
- ✓"Whose" shows possession no matter whether the owner is a person, an animal, or a thing.
Advanced Notes
In natural speech, "that" (or no pronoun at all) is far more common than "who" or "which" in defining clauses — "which" can sound slightly formal or bookish outside of contexts like "after a preposition" (the topic on which we agreed). Dropping the object relative pronoun ("the book I read") is the everyday default; keeping it ("the book that I read") just adds a touch of formality, never a grammar error either way. Because a defining clause supplies information the sentence needs to make sense, it is never set off by commas — adding one shifts the meaning toward non-defining and can quietly change what the sentence claims (compare "the students who passed celebrated" with "the students, who passed, celebrated").
FAQ
Who vs which vs that — which do I use?
Who is for people, which is for things, and that can replace either in defining clauses, especially in speech. Whose adds possession for people, animals, or things; where adds a place. Mixing them up — "the book who I read" or "the man which I met" — is the most common error at this level.
Can I say "the book who I read"?
No — "who" is only for people. For things, use "which" or "that": "the book that I read" or "the book which I read."
When can I drop who/which/that?
Only when the pronoun is the object of its own clause: "The film (that) we watched" — "we" is already the subject, so "that" is optional. If the pronoun is the subject of its clause, it must stay: "The man who called you" — dropping "who" leaves a broken sentence.
"The man who he called me" — what's wrong with this sentence?
It doubles the subject. "Who" already is the subject of "called," so adding "he" as well is redundant and incorrect. The correct sentence is "The man who called me," with no extra pronoun.
Do I need a comma before who/which/that?
No — in a defining (identifying) relative clause, there's no comma before who, which, that, whose, or where, because the clause is essential to identifying the noun. A comma is only used for non-defining clauses, which add extra, non-essential information.
Practice
- 1.The man called you is my brother.
- 2.I lost the keys were on the desk.
- 3.This is the house I grew up.
- 4.She's the girl dog won the competition.
- 5.He isn't the man lives next door.
Compare With
Other B1 Topics
Present Perfect
Used for past actions that still matter or connect to now
Present Perfect Continuous
Used for ongoing actions that started in the past and still continue
Modal Verbs
Expresses ability, obligation, permission, or possibility
Passive Voice (Basic)
Used for sentences where the action or result matters more than who did it
Used To
Used for past habits or states that no longer exist
Future Continuous
Used for actions in progress at a specific future moment
Question Tags
Used for confirming information or seeking agreement at the end of a statement
Linking Words: However, Although, Despite, In Spite Of
Used for connecting contrasting ideas using concession and contrast markers
So and Such
Use so before adjectives/adverbs and such before nouns to emphasize degree, often followed by a that-clause showing the result.
Order of Adjectives
The fixed order adjectives usually follow before a noun: opinion, size, age, shape, colour, origin, material, purpose.
Future Time Clauses
Use present simple, not will, after when/as soon as/before/after/until/once even when the meaning is future.
Subject and Object Questions
Who broke it? vs Who did you see? — question word as subject or object.