B1 · Lesson 15 · 20 min
Non-defining relative clauses: Adding extra information
Add useful extra information with who, which and whose, separating the clause with commas. Learn why you cannot use that or leave out the relative pronoun in these clauses.
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In this lesson
- I can add extra information about people and things with non-defining relative clauses.
- I can use who, which and whose with commas, without that or an omitted relative pronoun.
Grammar in context
Maya is planning a small exhibition at the town library. Her brother Leo, who works as a photographer, has offered to take pictures. The library, which reopened last month, has a bright new gallery. Maya will also invite Mrs Patel, whose paintings are popular locally.
Which details identify the people and places, and which details simply add extra information?
Extra information and commas
A non-defining relative clause gives extra information about a person, thing or place that is already clear. Put commas around the extra information. If you remove the clause, the main sentence still makes sense and identifies the person or thing. In speech, we usually pause before and after the extra information.
- My aunt, who lives in Bristol, is visiting on Friday.
- The red bus, which stops outside the museum, is late again.
Who, which and whose
Use who for people and which for things, animals and whole ideas. Use whose to show possession. The noun after whose belongs to the person or thing before it. These clauses can come in the middle of a sentence or at the end, but the commas are still important.
- Daniel, whose phone was missing, checked the café twice.
- We chose the earlier train, which was less crowded.
No that and no omitted pronoun
Do not use that in a non-defining relative clause. Also, do not leave out who, which or whose, even when it is the object of the clause. This is different from some defining relative clauses, where that or no pronoun can be possible. Keep the relative pronoun after the first comma.
- Our guide, who I met yesterday, knows the area well.
- The film, which we watched after dinner, was surprisingly funny.
Common mistakes
Compare the incorrect and corrected forms.
Avoid
My neighbour, that has a dog, is away.
Use
My neighbour, who has a dog, is away.
Use who, not that, for extra information about a person.
Avoid
The laptop, I bought last week, is already slow.
Use
The laptop, which I bought last week, is already slow.
Do not omit which in a non-defining relative clause.
Put it into practice
Try the exercises, write your own examples and check your understanding.