Understanding Relative Pronouns: Their Types and Functions

General Idea of Relative Pronouns

In English, there are five classic relative pronouns:

• who
• whom
• whose
• which
• that

Relative pronouns are used in a grammatical construction in which a noun is modified by a clause that comes after it. Here is a simple example:

The man who is playing with children is my husband.

If we break the sentence into its components, we get the following structure:

• Subject: The man (who is playing with children)
• Verb: is
• Complement: my husband.

This sentence forms a clear SVC structure with a relatively long subject.

A relative clause functions like an adjective because it describes or modifies a noun. In this sentence, the clause “who is playing with children” modifies the noun “man.”

Note that the main purpose of this sentence is to identify the speaker’s husband, not to describe the action of playing with children. The phrase “who is playing with children” simply helps identify which man the speaker is referring to.

This type of clause is called a relative clause, which begins with a relative pronoun such as who, which, or that. A relative clause provides additional information about a noun, but the core meaning of the sentence is expressed in the main clause.

Relative Clause

A relative clause is a type of dependent clause that modifies a noun that appears before it. Because it is a clause, it contains both a subject and a verb. In most cases, a relative clause begins with a relative pronoun, such as who, which, or that. However, a relative clause is omitted when a special construction is applied.

If you are unfamiliar with the distinction between independent and dependent clauses, the following article will help you understand it better.

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Consider the following example:

My dog, which runs fast, is cute.

We can divide the sentence as follows:

• Main independent clause: My dog is cute.
• Relative clause: which runs fast

In some relative clauses, the relative pronoun itself functions as the subject of the clause. In this example, the relative pronoun “which” refers to the antecedent “my dog” and acts as the subject of the verb runs.

Since a relative clause cannot stand alone as a complete sentence, it is considered a dependent clause. Therefore, it must be attached to an independent clause to form a complete sentence.

Classic Relative Pronouns

Five of the common relative pronouns are worth remembering, not only for reading but also for improving speaking and writing proficiency.

• who
• whom
• whose
• which
• that

Let’s explore how to effectively use these five relative pronouns.

Who

The relative pronoun “who” is used to refer to a person. It introduces a relative clause that modifies a noun referring to a person.

Note that “who” is primarily used for people, although it may sometimes be used for animals when they are treated as individuals.

Here is an example:

My teacher, who laughs a lot, is liked by many students.

In this sentence, the antecedent of the relative pronoun “who” is the noun “my teacher,” which refers to a person. This is why the relative pronoun “who” is used in this sentence.

Whom

Among relative pronouns, “whom” is perhaps the trickiest one. The relative pronoun “who” is used when it functions as the subject of the relative clause. For example,

I like my father who always cheers me up.

In the relative clause,

• Subject: who (my father)
• Verb: always cheers
• Object: me

In the clause “who always cheers me up,” the relative pronoun “who” functions as the subject of the verb cheers. This relative clause can be rewritten as the following independent sentence:

My father always cheers me up.

However, “whom” is used when the relative pronoun functions as the object of the relative clause.

Let’s check how this grammatical element is used:

I like my father whom my sister hates.

In the relative clause,

• Subject: my sister
• Verb: hates
• Object: whom (= my father)

You may notice that this time the relative pronoun “whom” serves as the object of the relative clause.

So, depending on the role of the relative pronoun in the clause, you must determine whether “who” or “whom” is appropriate.

Here’s another example sentence with relative pronoun “whom”:

I know the man whom my sister is talking to.

In the relative clause,

• Subject: my sister
• Verb: is talking to
• Object: whom (= the man)

Again, in this sentence, the antecedent of the relative pronoun does not function as the subject of the relative clause; rather it functions as the object of the relative clause.

When this happens, we must use “whom” instead of “who” to introduce a relative clause.

Whose

“Whose” is the possessive form of a relative pronoun. It is used to indicate possession in a relative clause.

In other words, “whose” shows that something belongs to the antecedent.

Note that “whose” is not limited to people. It can also be used to refer to animals or things when possession is expressed.

Here is an example:

I have a dog whose eyes are as beautiful as jewels.

In the relative clause “whose eyes are as beautiful as jewels,” the relative pronoun “whose” shows that the eyes belong to the dog. Even though the antecedent “dog” is not a person, “whose” can still be used because the clause expresses possession.

You can rewrite the idea in the relative clause as an independent sentence:

The dog’s eyes are as beautiful as jewels.

Here, it is clear that “the dog’s eyes” is in the possessive form. Therefore, when we express the same idea using a relative clause, we use the relative pronoun “whose.”

Which

While “who” is used to refer to people, the relative pronoun “which” is commonly used to refer to animals, objects, or ideas. For example, if you want to add information about a dog, you can use “which.”

I have a dog which has beautiful eyes.

In this sentence, the relative clause “which has beautiful eyes” describes the noun “dog.” In general, “which” is used for non-human antecedents, while “who” is used for people.

That

You can think of the relative pronoun “that” as a joker in a card game. It can function like both “who” and “which” in many situations.

Instead of deciding whether to use “who” or “which,” you can often use “that” to introduce a relative clause.

I have a dog that has beautiful eyes.

Because “that” can refer to both people and things, it is often used in everyday English.

However, “that” cannot be used in some situations, such as in non-restrictive relative clauses or immediately after a preposition.

For this reason, in formal writing or English tests, it is often better to choose “who” or “which” depending on the antecedent.

Restrictive vs Non-Restrictive Clauses

When you use a relative pronoun, you must consider the difference between restrictive and non-restrictive clauses. Many learners think this distinction is complicated, but it is actually quite simple once you understand the idea.

• Restrictive clause: the clause is essential to the meaning of the sentence.
• Non-restrictive clause: the clause adds extra information and is not essential to the meaning.

Consider the following two sentences.

Restrictive clause

I have three daughters who can play piano.

This sentence implies that I may have more than three daughters, but three of them can play piano.

Non-restrictive clause

I have three daughters, who can play piano.

You can think of the comma as a slight separation of meaning. In this sentence, the main statement “I have three daughters” already provides complete information. The clause “who can play piano” simply adds additional information.

Therefore, this sentence suggests that all three daughters can play piano.

Restrictive clauses are not separated by commas, while non-restrictive clauses must be enclosed by commas.

Special Use of “Which” in Non-Restrictive Clauses

In addition to modifying a noun directly, “which” can also be used to refer to an entire clause or situation. This usage appears in non-restrictive relative clauses, and it is always separated by a comma.

Look at the following example:

My car broke down, which surprised me.

In this sentence, “which” does not refer to a single noun. Instead, it refers to the entire previous statement:

My car broke down.

Therefore, the sentence means:

My car broke down, and this situation surprised me.

Because this type of clause simply adds additional information about the previous statement, it is always treated as non-restrictive, and a comma must be used before “which.”

Important Note

When “which” refers to an entire clause, it cannot be replaced by “that.”

✓ The meeting was canceled, which disappointed everyone.

× The meeting was canceled, that disappointed everyone.

This is because “that” cannot be used in non-restrictive relative clauses.