Relative clauses
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FormGeneral usage
Defining versus non-defining
Quizzes for relative clauses
Resource index for relative clauses
Form
noun (+ relative pronoun) + relative clause
noun, + relative pronoun + relative clause, + main clause
main clause, relative pronoun + relative clause
noun, + relative pronoun + relative clause, + main clause
main clause, relative pronoun + relative clause
There are two kinds of relative clauses
Relative clauses contain information about nouns. There are two main types: defining and non-defining. The form and usage of each is quite different. Have you seen the book that I was reading this morning?
This is a defining relative clause and contains information about the noun book. The River Nile, which is over 6,500 kilometres long, is Egypt's main source of water.
This is a non-defining relative clause and contains information about the noun the River Nile.
The information in the first example, that I was reading this morning, identifies the book - it tells us which book. The information in the second example, which is over 6,500 kilometres long, is extra information.
The main differences between the two types of clauses are summarised below.
This is a defining relative clause and contains information about the noun book.
This is a non-defining relative clause and contains information about the noun the River Nile.
Identifying (saying which or what kind of) versus extra information
The main differences between the two types of clauses are summarised below.
Defining versus non-defining relative clauses
Defining relative clauses
Non-defining relative clauses
- identify a noun - i.e. tell us which or what kind of person, place or thing we are talking about
- are not separated by commas
- use the pronouns which or that for things and who or that for people
- can be formed without a relative pronoun when the pronoun is not the subject of the relative clause
- cannot be removed from a sentence, otherwise the sentence will be ungrammatical or unclear
- are common in both spoken and written English
- give extra information about a person, place, thing etc.
- are separated by commas
- do not use that as a relative pronoun
- are always formed with a relative pronoun
- can be removed from a sentence and the sentence will still be grammatical
- are more common in written English and formal spoken English (speeches, TV news reports etc.)
For more, see detailed notes on each type of relative clause:
defining relative clauses
non-defining relative clauses
ESL quizzes for relative clauses
