A kind of relative clause, a non-defining relative clause, tells us about the subject of a sentence, but the knowledge doesn’t help to define what we’re talking about.
The information included in the clause is extra: it’s not essential for understanding the sentence. For this reason, a non-defining relative clause might also be called a non-essential relative clause.
Take a look at this example:
- The garden, which was full of blossoming flowers, overlooked the hill.
In this sentence, the clause ‘which was full of blossoming flowers’ is a non-defining relative clause. It’s not essential for understanding the rest of the sentence, but it helps to paint a clearer picture. It doesn’t define the garden either – it just gives us something extra. If we removed the non-defining relative clause from the sentence, like so:
- The garden overlooked the hill.
It still makes complete grammatical sense.
How do you write a Non-Defining Relative Clause?
Non-defining relative clauses contain a few main things: a relative pronoun, a verb, and other optional elements, such as the verb’s subject. It would help if you used commas, hyphens, or brackets to split the non-defining relative clause from the rest of the sentence.
The clause most commonly appears in the middle or end of a sentence.
Which relative pronouns can you use in a Non-Defining Relative Clause?
It would be best if you used the following pronouns: who, whose, whom, which, and where.
How is a Non-Defining Clause different from a Defining Relative Clause?
As we’ve already established, the information in a non-defining relative clause is non-essential. So, that means the information in a defining relative clause is essential. Here are some other key differences between the two:
- In a defining relative clause, the relative pronouns who, whom, and which are often replaced with ‘that’ in spoken English. You can’t do this with a non-defining relative clause.
- In a non-defining relative clause, the pronoun must always be included. However, it can sometimes be removed from a defining relative clause.
- Defining relative clauses use no punctuation, whereas non-defining ones need to be separated from the other clause(s) using commas, hyphens, or brackets.
Here is an example to compare.
| Non-defining | Defining | Explanation |
| She gave me a cupcake, which was red velvet flavored. | She gave me a cupcake that was red velvet flavored. | The first example gives extra information about a single cupcake. The relative pronoun ‘which’ is used, as well as a comma.
The second example specifies which cupcake was given – implying that there are multiple cupcakes. The relative pronoun ‘that’ is used, and there’s no punctuation with the relative clause. |
Non-Defining Clause Introductory Expressions
Sometimes, a non-defining relative clause can be introduced by an expression followed by a relative pronoun (whom or which). These are some of the phrases that you can use:
- all of;
- any of;
- some of;
- a few of them;
- much of;
- each of;
- both of;
- either of;
- half of;
- many of;
- much of;
- one of;
- two of;
- none of.
Here’s how you can use them in a sentence:
- I collect stamps, many of which are vintage.
- I have lots of cousins, some of whom live abroad.
