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What Is a Relative Clause?
Definition of "Relative Clause" (with Examples)A relative clause is a multi-word adjective that includes a subject and a verb. For example:
- The nightingale that we fed last year has returned. (The relative clause "that we fed last year" is functioning as an adjective describing "the nightingale." The subject of the clause is "we," and the verb is "fed.")
Table of Contents
- Examples of Relative Clauses
- The Traits of a Relative Clause
- Dropping the Relative Pronoun
- Why Relative Clauses Are Important
- Printable Test
A relative clause comes after the noun it modifies and is made up of several words, which (like all clauses) include a subject and a verb.
Examples of Relative ClausesHere are some examples of relative clauses:
- The windows that you installed last year have warped.
- Kindness is the language which the deaf can hear and the blind can see. (Writer Mark Twain)
- The follies which a man regrets most in his life are those which he didn't commit when he had the opportunity. (US journalist Helen Rowland) (Even though this is a quotation by an American journalist, nowadays, most writers in the US would use "that" instead of "which." There's more on this below.)
The Traits of a Relative ClauseA relative clause has the following three traits: A relative clause is headed by a relative pronoun ("who," "whom," "whose," "that," or "which") or a relative adverb ("when," "where," or "why"), which links it to the noun it is modifying.
Quite often, the relative pronoun can be omitted. However, with a relative clause, it is always possible to put one in. (There is more on this below.)
More about the Three Traits of a Relative Clause
Look at the three traits in this example:
Here are two common questions related to relative clauses.
Often, the relative pronoun is the subject of the clause. Look at the three traits in this example:
Dropping the Relative Pronoun
It is common for the relative pronoun to be omitted. For example:
This is not always possible though:
- The windows
that you installed last year have warped.
- The film
which you recommended scared the kids half to death.
- The follies
which a man regrets most in his life are those which he didn't commit when he had the opportunity. (Helen Rowland, 1876-1950)
When the relative clause starts with a relative adverb ("when," "where" or "why"), the relative adverb cannot be omitted.
- Bore: a person
who talks when you wish him to listen.
- There comes a time when money doesn't matter. (Boxer Floyd Mayweather)
(You can often omit a relative pronoun, but you can't omit a relative adverb. So, you can't omit "when" in this example.)
(Question 1) Should I use a comma before "which?This is the most common question related to relative clauses. The answer is sometimes yes and sometimes no. The answer applies to all relative clauses, not just those that start with "which."
This is the rule:
- Do not put commas around your clause if it is essential; i.e., it is required to identify its noun. (This is called a restrictive clause.)
- Do use commas if your clause is just additional information. (This is called a non-restrictive clause.)
- My brother, who claimed to have a limp, sprinted after the bus. (This clause is not required to identify "My brother." It is just additional information.)
- My brother (who claimed to have a limp) sprinted after the bus. (As it's just additional information, you can put it in brackets.)
- My brother sprinted after the bus. (As it's just additional information, you can even delete it.)
- A burglar who fell through a garage roof is suing the house owner. (This clause is required to identify "a burglar." Without it, we don't know which burglar we're talking about.)
- The tramp (who claimed to have a limp) sprinted after the bus. (This sentence is only appropriate if we know which tramp we're talking about.)
- The tramp sprinted after the bus. (This sentence is only appropriate if we know which tramp we're talking about.)
(Question 2) What's the difference between "that" and "which"?"Which" and "that" are interchangeable, provided we're talking about "which" without a comma.
When "which" starts a restrictive clause (i.e., a clause not offset with commas), you can replace it with "that." In fact, Americans will insist you use "that" instead of "which" for a restrictive clause.
- Mark's dog which ate the chicken is looking guilty. (but in America or at least widely disliked) (Americans baulk at "which" without a comma. They insist on "that.")
- Mark's dog that ate the chicken is looking guilty. (This version is acceptable for all. It will stop you getting hate mail from Americans.)
The "that substitution" trick also works with "who," but be aware that some of your readers might not like that used for people.
- The burglar who is suing the homeowner was booed in court.
- The burglar that is suing the homeowner was booed in court. (Substituting "who" for "that" is a good way to test whether an adjective clause needs commas or not, but some of your readers might not like "that" being used for a person – even a burglar. So, if your clause starting "who" sounds okay with "that," then revert to "who" without commas.)
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