Relative clauses

A relative clause is a small clause that comes right after a noun to say which person or thing you mean, or to add information about it. It starts with a relative pronoun (who, which, that). The pronoun replaces he / she / it / they…, so you don't repeat that subject or object.

• I have a neighbour. She grows vegetables on her roof. → I have a neighbour who grows vegetables on her roof.

  who replaces she

• We bought a fan. It's really quiet. → We bought a fan which is really quiet.

  which replaces it

• The man who fixed my bike didn't charge me anything.

Choose the pronoun with two questions: is the noun before it a person or a thing, and is the pronoun the subject or the object of the clause? Ø means you can leave the pronoun out.

• I want a phone which takes good photos at night.

• Do you know anyone that speaks Korean?

• The dog that lives next door barks at everyone.

That works for both people and things and is very common in speech. For people, who is more usual in writing. In American English many writers prefer that to which when the clause has no commas; British English uses both.

💡When the relative pronoun is the subject of the clause, you can't leave it out: People who live near the river worry about floods (not: People live near the river worry…). Without who, the sentence has two main verbs and no clear structure.

If the relative pronoun is the object — that is, another subject (I, you, my mum…) comes right after it — you can leave it out. Native speakers do this all the time in speech.

• The cake (that) my mum made was delicious.

  that is the object of made → can be dropped

• Is this the charger you were looking for?

• The people I work with are really friendly.

• The woman who called you left a message.

  who is the subject of called → can't be dropped

Watch the preposition: in everyday English it goes at the end of the clause (the people I work with, the flat we live in). In formal writing you can move it to the front, but then you must use whom or which, not that: the people with whom I work, the flat in which we live.

There are two kinds of relative clause. A defining clause tells you which person or thing — without it the sentence isn't clear. A non-defining clause just adds information about someone or something the listener can already identify — without it the sentence still makes sense. It goes between commas (in speech, with short pauses).

• My cousin who lives in Canada is an engineer.

  suggests I have several cousins — this is the one in Canada

• My cousin, who lives in Canada, is an engineer.

  where he lives is just extra information

• Da Nang, which has a long sandy beach, is popular with families.

• We visited my grandmother, who turns 90 this year.

💡After a name (Da Nang, Mr Nam) or a noun there is only one of (my mother, the sun), a relative clause is almost always non-defining: use commas and don't use that.

, which can also refer to the whole idea before it, not just one noun. This always has a comma and only which is possible (not what or that).

• Lan passed her driving test first time, which surprised everyone.

• The bus was late again, which meant I missed the meeting.

• The verb in the clause agrees with the noun before it: a friend who lives…, two friends who live…, everyone who was there… (everyone is singular).
• After everything / anything / nothing / all / the only / a superlative, people usually use that or nothing: Is there anything (that) I can do? — the best film (that) I've ever seen.
• What means the thing(s) that and does not follow a noun: What I need is a holiday. But: everything that he said (not: everything what).
• Those who = the people who (fairly formal): Those who exercise regularly sleep better (not: They who…).
• For whose, where, when, why and whom, see the lesson “Relative clauses with whose / where / when”.

• ✗The girl who she sits next to me is from Hue.

  ✓The girl who sits next to me is from Hue.

  Who already replaces she — don't repeat it.

• ✗The bus goes to the airport leaves every 20 minutes.

  ✓The bus that goes to the airport leaves every 20 minutes.

  A subject pronoun can't be left out.

• ✗The film which I watched it last night was great.

  ✓The film (which) I watched last night was great.

  Which is already the object — drop it.

• ✗My father, that is a doctor, works in Hanoi.

  ✓My father, who is a doctor, works in Hanoi.

  No that in a clause between commas.

• ✗She didn't call me back, what was strange.

  ✓She didn't call me back, which was strange.

  Use which to refer to a whole idea.

• ✗Everything what he said was true.

  ✓Everything (that) he said was true.

  After everything, use that or nothing.