What are Relative Clauses?
A relative clause is a dependent clause that modifies or describes a noun or noun phrase in the sentence. There are two main types: defining (restrictive) clauses, which are essential to the meaning of the noun, and non-defining (non-restrictive) clauses, which add extra information. Defining clauses have no commas; non-defining clauses are set off by commas.
A relative clause is a clause that modifies a noun. Defining clauses ('The person who won') are essential and have no commas; non-defining clauses ('My brother, who is a doctor,') add extra detail and use commas.
- •The book that I read was excellent.
- •People who exercise live longer.
- •The student whose report was late apologized.
- •My book, which I bought yesterday, was excellent.
- •My brother, who is a doctor, lives in London.
- •The Eiffel Tower, which is in Paris, is famous.
Step-by-step worked examples
Identify the relative clause and type: 'The employee who submitted the report was promoted.'
Relative clause: 'who submitted the report'. Type: DEFINING (restrictive) — which employee? The one who submitted the report. No commas. Without this clause, the sentence is incomplete — we wouldn't know which employee.
Identify the relative clause and type: 'My sister, who lives in Paris, is a lawyer.'
Relative clause: 'who lives in Paris'. Type: NON-DEFINING (non-restrictive) — set off by commas. Extra information about my sister. Without this clause, the sentence is still complete: 'My sister is a lawyer.'
Identify the relative clause and type: 'The city that we visited last summer was beautiful.'
Relative clause: 'that we visited last summer'. Type: DEFINING — which city? The one we visited last summer. No commas. This clause is essential to specify which city.
Flashcards
Quick quiz
Q1.Which sentence uses a defining relative clause?
Q2.Which uses a non-defining relative clause?
Q3.Why should you NOT use 'that' here?: 'My best friend, ___ is a musician, won an award.'
Q4.What does removing the relative clause do?: 'The restaurant, which serves sushi, is downtown.'
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Common mistakes
Using 'that' in non-defining clause: 'My brother, that is a doctor, helps people.' — Correct: Use 'who' in non-defining (with commas): 'My brother, who is a doctor, helps people.'
Adding commas around defining clause: 'The person, who solved it, got a prize.' — Correct: No commas: 'The person who solved it got a prize.' (defining — essential to say which person)
Confusing that both types use the same pronouns: 'The time when I was young' vs 'My childhood, when I was young'. — Correct: Both can use 'when'. The difference is commas: defining (no commas, essential) vs non-defining (commas, extra).
Omitting 'whom' for the object: 'The author that I met was famous.' — Correct: In formal English: 'The author whom I met was famous.' (though 'that' is increasingly used in speech).
FAQ
What is a relative clause?
A clause that modifies a noun, beginning with 'who', 'whom', 'which', 'that', 'whose', 'where', or 'when'. Defines or adds info about the noun.
Defining vs non-defining — how do commas show the difference?
Defining (no commas): 'The student who studied passed.' Essential to identify which student. Non-defining (commas): 'My friend, who studied hard, passed.' The clause is extra info; the sentence works without it.
Can I always use 'that'?
'That' is used in defining clauses only: 'the book that I read'. In non-defining, use 'which' (things) or 'who' (people) with commas: 'my book, which is blue'.
When do I use 'whose' in relative clauses?
'Whose' shows possession: 'The student whose name is Alex' (defining) or 'My colleague, whose office is next door' (non-defining, with commas).