Relative Clauses

Master relative clauses to build more sophisticated sentences. Learn relative pronouns, defining vs non-defining clauses, and when to omit pronouns.

Level B1-B2-C1-C2⏱️ 55 min📋 Requires: Pronouns, Basic sentence structure, Verb tenses

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Relative clauses are subordinate clauses that provide extra information about a noun. They let us combine sentences and create more sophisticated, fluent text — essential from B1 level upward.

📋 Quick Reference

1Defining clauses: essential information (no commas)

2Non-defining clauses: extra information (with commas)

3Relative pronouns: who, which, that, whose, where, when

4Can be omitted in certain cases

5Prepositions can go at the end or before the pronoun

Relative pronouns connect the relative clause to the noun they modify.

Relative Pronouns and Their Uses

Pronoun	Refers to	Function	Example
who	People	Subject or object	The man who lives next door
whom	People (formal)	Object	The person whom I met
which	Things/animals	Subject or object	The book which I read
that	People/things	Subject or object	The car that I bought
whose	Possession	Possessive	The woman whose car broke down
where	Places	Adverbial	The place where we met
when	Time	Adverbial	The day when it happened
why	Reason	Adverbial	The reason why I left

🇪🇸 Spanish:

El hombre que vive al lado es médico.

🇬🇧 English:

The man who lives next door is a doctor.

📝 Translation:

'Who' refers to a person (subject)

🇪🇸 Spanish:

El libro que leí era interesante.

🇬🇧 English:

The book that/which I read was interesting.

📝 Translation:

'That/which' refers to a thing (object)

💡

Remember: Use 'who' for people, 'which' for things, and 'that' for both (more informal).

The difference between defining and non-defining clauses affects meaning and punctuation.

Types of Relative Clauses

Type	Function	Punctuation	Example
Defining	Essential information to identify	No commas	The students who study hard pass exams
Non-defining	Extra, non-essential information	With commas	My brother, who lives in London, is a doctor
Defining	Specifies which one exactly	No commas	The car that I bought is red
Non-defining	Adds extra information	With commas	This car, which cost £20,000, is very reliable

Important rules for defining vs non-defining

Key differences between both types:

Examples:

Defining: do NOT use commas — information is necessary
Non-defining: DO use commas — information is optional
Defining: you can use 'that'
Non-defining: you cannot use 'that', only who/which
Defining: you can omit the pronoun (when object)
Non-defining: NEVER omit the pronoun

🇪🇸 Spanish:

Los estudiantes que estudian mucho aprueban. (defining - especifica qué estudiantes)

🇬🇧 English:

The students who study hard pass.

📝 Translation:

No commas — essential information

🇪🇸 Spanish:

Los estudiantes, que estudian mucho, aprueban. (non-defining - todos los estudiantes)

🇬🇧 English:

The students, who study hard, pass.

📝 Translation:

With commas — additional information

In defining clauses, we can sometimes omit the relative pronoun for more natural English.

When to omit relative pronouns

Only in defining clauses when the pronoun is the object:

Examples:

The book (that/which) I read → The book I read
The person (who/that) I met → The person I met
The car (that/which) he bought → The car he bought

Omitting Pronouns

Function	Can be omitted	With pronoun	Without pronoun
Object	✅ Yes	The book that I read	The book I read
Subject	❌ No	The man who called	❌ The man called
With preposition	✅ Yes (informal)	The house that I live in	The house I live in
Possessive (whose)	❌ No	The woman whose car...	❌ The woman car...

✅

Tip: If you can remove the pronoun and the sentence still makes sense, it was the object and can be omitted.

Prepositions can go at the end of the clause (informal) or before the pronoun (formal).

Position of Prepositions

Style	Structure	Example	Register
Informal	Preposition at the end	The house (that) I live in	Conversational
Formal	Preposition + whom/which	The house in which I live	Academic/written
Informal	Preposition at the end	The person (who) I talked to	Conversational
Formal	Preposition + whom	The person to whom I talked	Academic/written

🇪🇸 Spanish:

La casa en la que vivo es antigua. (informal)

🇬🇧 English:

The house I live in is old.

📝 Translation:

Preposition at the end, pronoun omitted

🇪🇸 Spanish:

La casa en la que vivo es antigua. (formal)

🇬🇧 English:

The house in which I live is old.

📝 Translation:

Preposition before the pronoun

⚠️

Watch out! With prepositions at the start, use 'whom' (people) or 'which' (things), never 'who' or 'that'.

These relative pronouns refer to place, time, and reason respectively.

Where, When, Why in Relative Clauses

Pronoun	Replaces	Example	Formal alternative
where	in/at/on + which	The place where we met	The place at which we met
when	in/on/at + which	The day when it happened	The day on which it happened
why	for which	The reason why I left	The reason for which I left
where	in/at + which	The school where I studied	The school at which I studied

🇪🇸 Spanish:

Esta es la ciudad donde nací.

🇬🇧 English:

This is the city where I was born.

📝 Translation:

'Where' = in which

🇪🇸 Spanish:

¿Recuerdas el día cuando nos conocimos?

🇬🇧 English:

Do you remember the day when we met?

📝 Translation:

'When' = on which

🇪🇸 Spanish:

No entiendo la razón por la que se fue.

🇬🇧 English:

I don't understand the reason why he left.

📝 Translation:

'Why' = for which

❌

Error: "The man, that lives next door, is nice" ❌
Correct: "The man, who lives next door, is nice" ✅
Do not use 'that' in non-defining clauses

❌

Error: "The book what I read" ❌
Correct: "The book that/which I read" ✅
'What' is not a relative pronoun in this context

❌

Error: "The woman whose I met" ❌
Correct: "The woman who I met" or "The woman whose husband I met" ✅
'Whose' is only for possession

❌

Error: "The place where I went to" ❌
Correct: "The place where I went" or "The place I went to" ✅
Do not use an extra preposition with 'where'

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Relative Clauses