Relative clauses are used to connect a clause or phrase to a noun or pronoun, providing essential or additional information about it. There are two main types of relative clauses: defining and non-defining.
- Defining relative clauses specify which person or thing we are talking about and are essential to the meaning of the sentence.
- Non-defining relative clauses add extra information that is not essential to the main message; the sentence would still make sense without it.
Defining Relative Clauses
A defining relative clause provides essential information needed to identify the noun it refers to. Without this clause, the meaning of the sentence would be incomplete or unclear.
- The relative clause tells us exactly which person or thing is meant.
- You do not use commas for defining relative clauses.
- Common relative pronouns: who (for people), which (for things), that (for people or things).
Examples:
- The woman who lives next door is a doctor.
(The clause “who lives next door” tells us which woman.)
- I want to buy the book that you recommended.
(The clause “that you recommended” tells us which book.)
- Cars which have electric engines are becoming more popular.
(The clause “which have electric engines” tells us which cars.)
Exercise 1
Identify the relative clause in each sentence and say whether it is defining or non-defining:
- People who eat vegetables tend to be healthier.
- My father, who is a pilot, travels a lot.
- The movie that we saw last night was fantastic.
- London, which is the capital of England, is very crowded.
Defining
No
Yes
Non-defining Relative Clauses
A non-defining relative clause adds extra, non-essential information about a noun that has already been clearly identified. The sentence would still make sense if the clause were removed.
- Non-defining clauses are always separated by commas.
- Common relative pronouns: who (for people), which (for things), whose (for possession).
- You do not use that in non-defining relative clauses.
Examples:
- My brother, who lives in New York, is visiting us next week.
(The clause “who lives in New York” adds extra information about my brother.)
- The Eiffel Tower, which is in Paris, is a famous landmark.
(The clause “which is in Paris” adds extra information about the Eiffel Tower.)
- Sarah, whose car was stolen, reported it to the police.
(The clause “whose car was stolen” adds extra information about Sarah.)
Exercise 2
For each sentence below, decide if the relative clause is non-defining and whether the commas are used correctly:
- Mr. Smith, who is our teacher, will give a test tomorrow.
- I have a friend who can speak six languages.
- Paris, which is known as the City of Lights, is beautiful in the spring.
- The laptop that I bought last week is already broken.
No
Yes
who, which, whose
Summary
| Feature | Defining Relative Clauses | Non-defining Relative Clauses |
|---|---|---|
| Purpose | Identify/define the noun | Add extra information |
| Are commas used? | No | Yes |
| Can the clause be removed? | No, essential for meaning | Yes, information is additional |
| Relative pronouns | who, which, that, whose | who, which, whose |
| Example | The man who talks is funny. | My uncle, who talks, is funny. |
Conclusion
Defining and non-defining relative clauses serve different purposes: defining clauses are essential for identifying the noun and do not use commas, while non-defining clauses add extra information and are set off by commas.
- Defining clauses are essential; non-defining clauses add extra info.
- Use no commas for defining clauses; use commas for non-defining.
- Common pronouns: defining (who, which, that), non-defining (who, which, whose).