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Defining and non-defining relative clauses

Learn how to use relative clauses to identify people or things, or to give extra information.

LEARNING GOALS
  • check_circleI can use defining relative clauses to identify exactly who or what I am talking about.
  • check_circleI can use non-defining relative clauses to add extra, non-essential information.
B115 min
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PART 01

Discover

Meet today's English in a real situation — no rules yet. Read it once and try to guess the pattern in the words in bold. Underlined words open a short definition.

format_quoteEXAMPLE

Anna: Have you seen the laptop that I left on the kitchen table?

Ben: No, I haven’t. But I saw the tablet, which is usually on the sofa.

Anna: Oh, I need the laptop. The client who called me yesterday is waiting for the report.

Ben: Is that the client whose company makes eco-friendly shoes?

Anna: Yes! By the way, Mr. Smith, who is their CEO, will visit us next week to discuss a partnership.

Ben: Great. Well, maybe you left the laptop in the lobby, where we had our morning coffee.

Anna: Good idea, I’ll go check!

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PART 02

Learn

Now the rules behind what you just saw — explained simply, with examples. Underlined words open a short definition — hover on desktop, tap on a phone.

Relative clauses give us more information about someone or something. We use relative pronouns like who, which, that, whose, and where to connect the clause to the main sentence. There are two types: defining and non-defining.

1. Defining Relative Clauses

These clauses give essential information to help us identify exactly who or what we are talking about.

  • We do not use commas.
  • We can use that instead of who or which.
  • We can sometimes omit (leave out) the relative pronoun if it is the object of the clause.
format_quoteEXAMPLE
  • The woman who/that lives next door is a doctor. (We need this clause to know which woman.)
  • The laptop which/that I bought yesterday is already broken.
  • The man I saw yesterday is my uncle. (We omitted who/that because ‘man’ is the object.)

2. Non-defining Relative Clauses

These clauses give extra, non-essential information. If we remove the clause, the sentence still makes sense and we still know who or what is being talked about.

  • We must use commas before and after the clause (or a comma and a period at the end).
  • We cannot use that.
  • We cannot omit the relative pronoun.
format_quoteEXAMPLE
  • My grandmother, who is 80 years old, goes swimming every day. (We already know who my grandmother is; her age is extra info.)
  • The Eiffel Tower, which was built in 1889, is in Paris. (We cannot say “that was built in 1889”.)
warningWARNING

Do not use that in non-defining relative clauses.

  • My car, that is very old, keeps breaking down.
  • My car, which is very old, keeps breaking down.

3. Whose and Where

We use whose to show possession (instead of his/her/their), and where for places. We can use them in both defining and non-defining clauses.

lightbulbTIP

Remember that whose is used for both people and things.

  • The company whose CEO resigned is in trouble.
format_quoteEXAMPLE
  • The hotel where we stayed was excellent. (Defining)
  • Paris, where I met my husband, is a beautiful city. (Non-defining)
  • I have a friend whose sister is famous. (Defining)
  • Mr. Jones, whose son is in my class, is a great teacher. (Non-defining)
boltQUICK REVIEW
  • Defining: Essential info. No commas. Can use that.
  • Non-defining: Extra info. Needs commas. Cannot use that.
  • Who/That: For people.
  • Which/That: For things.
  • Whose: For possession.
  • Where: For places.
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PART 03

Practice

Try it yourself. You'll see right away whether you got it right, plus a short explanation of why.

0 / 3 correct
1. Choose the correct sentence:
2. Which relative pronoun correctly completes the sentence? 'My brother, ___ lives in London, is visiting us next week.'
3. Which sentence shows possession correctly?
draw
PART 04

Use It

Now make the language yours in a real task. Use the prompt below — the editor keeps a simple word count, and nothing is saved or graded.

PROMPT
Write a short paragraph describing a famous person and a landmark in your country, using at least one defining and one non-defining relative clause.
0 words
checklistCHECK YOURSELF

Before you finish — be honest. Can you do these now?