Relative clauses: defining relative clauses

Relative clauses: defining relative clauses

Do you know how to define who or what you are talking about using relative clauses? Test what you know with interactive exercises and read the explanation to help you.

Look at these examples to see how defining relative clauses are used.

Are you the one who sent me the email?
The phone which has the most features is also the most expensive.
This is the video that I wanted to show you.
The person they spoke to was really helpful.

Try this exercise to test your grammar.

Grammar test 1

Grammar B1-B2: Relative clauses – defining relative clauses: 1

Read the explanation to learn more.

Grammar explanation

Relative clauses give us information about the person or thing mentioned. 

Defining relative clauses give us essential information – information that tells us who or what we are talking about.

The woman who lives next door works in a bank. 
These are the flights that have been cancelled.

We usually use a relative pronoun or adverb to start a defining relative clause: who, which, that, when, where or whose.


We can use who or that to talk about people. that is more common and a bit more informal.

She's the woman who cuts my hair.
He's the man that I met at the conference.


We can use which or that to talk about things. that is more common and a bit more informal.

There was a one-year guarantee which came with the TV.
The laptop that I bought last week has started making a strange noise!

Other pronouns

when can refer to a time.

Summer is the season when I'm happiest.

where can refer to a place.

That's the stadium where Real Madrid play.

whose refers to the person that something belongs to.

He's a musician whose albums have sold millions. 

Omitting the relative pronoun

Sometimes we can leave out the relative pronoun. For example, we can usually leave out who, which or that if it is followed by a subject.

The assistant [that] we met was really kind.
   (we = subject, can omit that)

We can't usually leave it out if it is followed by a verb.

The assistant that helped us was really kind.
   (helped = verb, can't omit that)

Do this exercise to test your grammar again.

Grammar test 2

Grammar B1-B2: Relative clauses – defining relative clauses: 2

Language level

Average: 4.2 (70 votes)

Submitted by Pershing on Fri, 29/09/2023 - 18:17


Grammar confusions with the following sentences:
1. Don't drink more (wine) than is good for your health.
2. There are few books on the shelf but I know.
3. He drinks more than expects.

1. Is sentence 1 a relative clause, based on the grammar system?
2. Can "than" be a relativizer to introduce a relative clause? And are there any other less common relativizers except common ones like: that, which, who, when, where, pre+whom, whose+n, why.
3. Analyze the sentences listed grammatically plz, especially on what kind of clause they belong to.
I was told by some expert that sentences 1&2 were both relative clauses where "than" and "but" function as relativizers since they introduce the subordinate clause, complete the subordinate clause as subject or object. But i just think: sentence 2 is just a compound sentence with one object omitted, and sentence 3 is an adverbial clause with both subject and object in subcordinate clause omitted, based on some conventions of English. Sentence 1 is just intuitively correct but grammatically incomprehensible to me, and I can accept it as a relative clause introduced by "than" reluctantly.

Hello Pershing,

1. This construction (than + verb phrase without a subject) is one which generates a lot of debate. For example:

The construction is only used with the verb 'be' (here: 'is'). You cannot replace it with any other verb, though it doesn't have to be an adjective following it. For example:

Don't eat more than is on the plate.

To make a good impression you should stay longer than is required.


To make a good impression you should stay longer than you really want. [the second 'you' is needed here]

Since the construction only works in such narrow bounds I would be minded to see it as an atypical but correct form.


Sentence 2 does not appear correct to me. You should use 'that' or 'which' in place of 'but'. Alternatively, you could say '...but this I know.' However, this changes the meaning.


Sentence 3 is also not correct. You need a subject ('...than he expects', for example). Unless, that is, you want to say 'He drinks more than (he) expects', in the sense that the amount of drinking he does is greater than the amount of expecting he does. This would be a rather odd statement but possible. In this case 'than' is functioning as a conjunction.


2. No. See above for the explanation of 'that' in sentence 1.


3. I think I've summarised the constructions above.



The LearnEnglish Team

Submitted by Tokhish on Sun, 21/05/2023 - 16:28


Hello I have a sentence

Surgery that/which involves removing a tumour is not an example of cosmetic surgery.

Here 'that' and 'which', which one is grammatically correct in this sentence? And what is the difference between 'that' and 'which' in this sentence and other places? of course, for relative clauses.

Hi Tokhish,

They are both grammatically correct. Generally, as relative pronouns they are interchangeable. However, only "that" (not "which") can substitute for "who". Also, "which" is slightly more formal-sounding than "that", but it's not a huge difference.

I hope that helps.


LearnEnglish team

I have a comma question with WHICH
Is a comma necessary before WHICH in this sentence? Why or Why not?

The Women's Basic Coat comes in our most traditional fabric which is 100% polyester.

Thanks for your help!

Hello teacher1.unifae,

This looks like a non-defining clause to me -- it doesn't seem to be essential to identifying which fabric is being talked about. In other words, there is only one 'our most traditional fabric'. This fabric is 100% polyester. So yes, a comma is needed.

All the best,
LearnEnglish team

Submitted by mon_mon on Mon, 24/04/2023 - 23:34


Good evening
My question is: is there a correct order to be followed, when, in a defining sentence, two actions refer to same subject and happen simulteneously?
"The girl didn't look both sides of the street. She was texting"

Are both options correct?

'The girl who didn't look both ways of the street was texting'
'The girl who was texting didn't look both sides of the street'

Thanks in advance

Hello mon_mon,

Both are grammatically fine. Your choice depends on which action you see as the background event, so to speak, and which as the main or most interesting action - the background event is in the relative clause and the main action is in the main clause.



The LearnEnglish

Submitted by Gracy on Mon, 17/04/2023 - 07:18


Why did “ that that” use in the following sentence? Could you please explain?
That that may win him a bit more support from Asian neighbours like Thailand and China, which are less squeamish about his barbaric methods.

Hello Gracy,

I'm afraid it's impossible to say without knowing the context, especially what was said before this.

All the best,
LearnEnglish team