Relative Clauses
Relative clauses give additional information about a noun. They can be defining (essential) or non-defining (extra information). Both use relative pronouns like who, which, and that.
What is a relative clause?
A relative clause is a dependent clause that describes or identifies a noun. It is introduced by a relative pronoun: who, whom, which, that, whose, where, when, why.
Defining relative clauses
A defining (restrictive) relative clause identifies which person or thing is meant. It is essential to the meaning — remove it and the sentence becomes unclear. No commas.
The man who called you is my brother. (which man? — the one who called)
The book that she recommended was excellent.
The café where we met has closed down.
Non-defining relative clauses
A non-defining (non-restrictive) relative clause adds extra information about a noun that is already identified. It is not essential — the sentence makes sense without it. Always use commas.
My sister, who lives in Madrid, is a doctor. (extra information about my sister)
The Eiffel Tower, which was built in 1889, is 330 metres tall.
Relative pronouns
| Pronoun | Refers to | Example |
|---|---|---|
| who | People (subject) | The man who called is here. |
| whom | People (object, formal) | The woman whom I met was kind. |
| which | Things / animals | The car which broke down is old. |
| that | People or things (defining only) | The film that I watched was great. |
| whose | Possession (people/things) | The student whose essay won is talented. |
| where | Places | The city where I grew up is small. |
'That' in non-defining clauses: Never use 'that' in non-defining relative clauses — always use 'who' or 'which': My dog, that is old ✗ / My dog, which is old ✓.
Tip: Try removing the relative clause. If the sentence still makes clear sense, it's non-defining (use commas). If the sentence loses its specific meaning, it's defining (no commas).