Simple explanation
What is a defining relative clause? A defining relative clause gives essential information about a noun. It tells us exactly which person, thing, or place we mean. In “The woman who works at the bank is my aunt,” the clause “who works at the bank” identifies the woman. Without this information, the listener may not know which woman we are talking about. Why do we use defining relative clauses? Defining relative clauses help us connect related information instead of using several short sentences. For example, “I know a man. He speaks four languages.” can become “I know a man who speaks four languages.” This makes the relationship between the ideas clearer and the sentence more natural. Using who, which, and that We normally use who for people and which for things. In defining relative clauses, that can often replace who or which. For example, both “The woman who called me” and “The woman that called me” are possible. Similarly, we can say “The phone which I bought” or “The phone that I bought.” Using whose for possession Whose expresses possession or another close relationship. It is followed by a noun: “a student whose laptop was stolen.” It is especially common when the person or thing being described is connected to another person or object. Using where for places Where can introduce a relative clause after a place when the clause describes something that happens there. For example, “This is the café where we first met.” The relative clause identifies the café by connecting it with an event that happened there. Subject and object relative pronouns An important B1 skill is recognizing whether a relative pronoun is the subject or object of its clause. In “The man who lives next door,” who performs the action of living, so it is the subject and cannot be omitted. In “The man who I met yesterday,” I is the subject and who is the object of met. In this case, we can also say “The man I met yesterday.” When can we omit the relative pronoun? Who, which, and that can often be omitted when they are the object of the relative clause. “The book that I ordered arrived today” can therefore become “The book I ordered arrived today.” However, a subject relative pronoun cannot be omitted. We need that in “The book that explains the rule is useful” because that is the subject of explains. Commas and defining relative clauses We do not normally separate a defining relative clause from its noun with commas because the information is necessary to identify the noun. For example, “Students who arrive late must wait outside” refers specifically to students who arrive late. Relative clauses that provide additional rather than identifying information belong to the topic of non-defining relative clauses. Negative and question forms A defining relative clause can contain negative verbs and questions can contain defining relative clauses too. For example, “I need a phone that doesn't cost too much” contains a negative relative clause. In “Do you know anyone who can fix laptops?”, the whole sentence is a question, while “who can fix laptops” identifies the kind of person being asked about. The basic rules for choosing the relative word remain the same.
Grammar formula
Person as subject
person + who/that + verb + ...I need someone who can help me.
Thing as subject
thing + which/that + verb + ...We need a printer that works properly.
Relative pronoun as object
person/thing + who/which/that + subject + verb + ...The woman who I called was busy.
Object relative pronoun omitted
person/thing + subject + verb + ...The woman I called was busy.
Possession
person/thing + whose + noun + verb + ...I met a student whose brother lives in London.
Place
place + where + subject + verb + ...This is the shop where I bought my laptop.
Negative relative clause
noun + who/which/that + negative verb + ...I need a laptop that doesn't overheat.
Question containing a relative clause
question structure + noun + relative clauseDo you know anyone who speaks Japanese?
Core rules
- 1
Use who for people
Use who when the noun being identified is a person or group of people: “The teacher who helped me was very patient.”
- 2
Use which for things
Use which when the noun being identified is a thing: “The app which tracks my expenses is free.”
- 3
Use that for people or things
In defining relative clauses, that can often replace who or which: “The person that answered the phone was helpful” and “The shoes that I bought are comfortable.”
- 4
Use whose for possession
Use whose to express possession or a relationship between the noun and another noun: “I know a woman whose son studies abroad.”
- 5
Use where for places
Use where when the noun refers to a place and the relative clause describes what happens there: “This is the park where we play football.”
- 6
Omit an object relative pronoun when appropriate
When who, which, or that is the object of the relative clause, it can often be omitted: “The movie that we watched was great” can become “The movie we watched was great.”
- 7
Keep a subject relative pronoun
When the relative pronoun is the subject of the relative clause, it cannot be omitted: “The woman who works here is a doctor.”
- 8
Do not normally use commas
A defining relative clause contains essential identifying information, so it is not normally separated from its noun by commas.
Useful examples
The woman who lives next door is a doctor.
The woman living in the house next to mine is a doctor.
Who refers to the woman and is the subject of lives, so it cannot be omitted.
I need a phone that has a good camera.
I need a phone with a good camera.
That identifies the type of phone needed and is the subject of has.
The book which is on my desk belongs to Sara.
The book sitting on my desk is Sara's.
Which refers to a thing and is the subject of is.
The people who work here are very friendly.
The people working here are very friendly.
Who identifies which people the speaker means.
The jacket that I bought online is too small.
The jacket I ordered online doesn't fit because it is too small.
That is the object of bought, so it can be omitted: “The jacket I bought online...”
The restaurant where we had dinner was excellent.
The restaurant in which we ate dinner was excellent.
Where connects the restaurant with an event that happened there.
I have a friend whose parents live in Canada.
I have a friend, and that friend's parents live in Canada.
Whose expresses the relationship between friend and parents.
The laptop I use for work is five years old.
My work laptop is five years old.
The object relative pronoun has been omitted. A full version could use “that I use.”
Students who finish early can leave the room.
Students can leave the room if they are the ones who finish early.
The relative clause identifies the particular group of students.
The movie that we watched last night was surprisingly good.
The movie we saw last night was much better than expected.
That is the object of watched and can be omitted.
Anyone who wants to join the club must register online.
Every person interested in joining the club has to register online.
Who is the subject of wants and therefore cannot be omitted.
This is the website where I found the information.
This is the website on which I found the information.
Where connects the website with the action of finding the information.
I need a laptop that doesn't get too hot.
I need a laptop that stays reasonably cool when I use it.
A relative clause can be negative. That is the subject of the negative verb phrase “doesn't get.”
Do you know anyone who can repair my bike?
Can you think of a person who is able to fix my bike?
The main sentence is a question, while who introduces a defining relative clause identifying the type of person needed.
Common mistakes
- ❌ The man which works here is my uncle. ✅ The man who works here is my uncle. Man refers to a person, so who is appropriate. That is also possible in a defining relative clause, but which is not normally used for people.
- ❌ The woman who she lives upstairs is a teacher. ✅ The woman who lives upstairs is a teacher. Who is already the subject of lives. Adding she creates an unnecessary second subject.
- ❌ The book that it is on the table is mine. ✅ The book that is on the table is mine. That is the subject of the relative clause, so an additional subject pronoun such as it must not be added.
- ❌ The boy lives next door is my classmate. ✅ The boy who lives next door is my classmate. Who is needed because it is the subject of lives. Subject relative pronouns cannot be omitted.
- ❌ The café which we met was very quiet. ✅ The café where we met was very quiet. The meaning is that the meeting happened at the café. Where naturally expresses this relationship with a place.
- ❌ I know a girl who her brother is a pilot. ✅ I know a girl whose brother is a pilot. The sentence expresses a relationship between the girl and her brother, so whose is required.
- ❌ The shoes, that I bought yesterday, are uncomfortable. ✅ The shoes that I bought yesterday are uncomfortable. A defining relative clause provides essential identifying information and is not normally separated by commas.
- ❌ The woman I met her yesterday was very friendly. ✅ The woman I met yesterday was very friendly. The omitted relative pronoun is already understood as the object of met. Her must not be added as another object.
Learning tips
- First identify the noun before the relative clause: is it a person, thing, place, or a relationship involving possession?
- To decide whether who, which, or that can be omitted, identify the subject inside the relative clause.
- If a verb comes directly after who, which, or that, the relative pronoun is often the subject and cannot be omitted.
- If who, which, or that is followed by a separate subject such as I, you, she, or a noun, the relative pronoun is often an object and may be omitted.
- Use whose + noun for possession or close relationships instead of incorrect combinations such as “who his” or “who her.”
- Remember that defining relative clauses can contain affirmative or negative verbs and can appear inside statements or questions.
- Ask whether the information is necessary to identify exactly who or what you mean. If it is, a defining relative clause is probably appropriate.
Practise this topic
Interactive exercises for this topic are coming soon.
PlannedRelated grammar
Related dictionary words
Frequently asked questions
What is the difference between who and that in defining relative clauses?
For people, who is usually the clearest and most natural choice, but that can often be used in defining relative clauses too. For example, both “The man who called me” and “The man that called me” are possible.
When can I leave out who, which, or that?
You can often leave out the relative pronoun when it is the object of the relative clause. In “The book that I bought,” I is the subject and that is the object, so “The book I bought” is also correct.
How can I tell whether a relative pronoun is the subject or object?
Identify who or what performs the action in the relative clause. In “The woman who called me,” who performs the action and is the subject. In “The woman who I called,” I performs the action, so who is the object.
Can I use both which and that for things?
Yes. In defining relative clauses, both are possible in many contexts. For example, “The laptop which I bought” and “The laptop that I bought” are both grammatical.
What is the difference between who and whose?
Who refers to a person and functions as a subject or object in the relative clause. Whose expresses possession or another close relationship: compare “a woman who works here” with “a woman whose car is outside.”
Do defining relative clauses need commas?
Normally, no. The relative clause contains information needed to identify the person or thing. Non-defining relative clauses, which provide additional information, follow different punctuation rules.
When should I use where in a relative clause?
Use where when the noun refers to a place and the relative clause describes something happening there, as in “the school where I studied.”
Can a defining relative clause be negative?
Yes. The verb inside the relative clause can be negative just like a verb in another clause. For example, “I need a job that doesn't require weekend work” contains a negative defining relative clause.
Can I use a defining relative clause in a question?
Yes. For example, “Do you know anyone who speaks Spanish?” is a question containing the defining relative clause “who speaks Spanish,” which identifies the kind of person being asked about.