Defining and Non-Defining Relative Clauses
Use relative clauses to provide extra information. This information can either define something (defining clause), or provide unnecessary, but interesting, added information (non-defining clause).
Relative clauses can be introduced by:
a relative pronoun: who (whom), which, that, whose
no relative pronoun
where, why and when instead of a relative pronoun
You need to consider the following when deciding which relative pronoun to use:
Is the subject or object or possessive of a relative clause?
Does it refers to a person or an object?
Is the relative clause a defining or non-defining relative clause?
NOTE: Relative clauses are often used in both spoken and written English. There is a tendency to use non-defining relative clauses mostly in written, rather than in spoken, English.
You need to consider the following when deciding which relative pronoun to use:
Is the subject or object or possessive of a relative clause?
Does it refer to a person or an object?
Is the relative clause a defining or non-defining relative clause?
NOTE: Relative clauses are often used in both spoken and written English. There is a tendency to use non-defining relative clauses mostly in written, rather than in spoken, English.
Deciding Whether A Clause Is Defining Or Non-Defining
Defining Relative Clauses
The information provided in a defining relative clause is crucial in understanding the meaning of the sentence.
Example: The woman who lives in apartment No. 34 has been arrested. The document that I need has `important` written at the top.
The purpose of a defining relative clause is to clearly define who or what we are talking about. Without this information, it would be difficult to know who or what is meant.
Example: The house is being renovated.
In this case it is not necessarily clear which house is being renovated.
Non-defining Relative Clauses
Non-defining relative clauses provide interesting additional information which is not essential to understanding the meaning of the sentence.
Example: Mrs. Jackson, who is very intelligent, lives on the corner.
Correct punctuation is essential in non-defining relative clauses. If the non-defining relative clause occurs in the middle of a sentence, a comma is put before the relative pronoun and at the end of the clause. If the non-defining relative clause occurs at the end of a sentence, a comma is put before the relative pronoun.
NOTE: In defining relative clauses there are no commas.
Relative Pronouns Used As The Subject of Defining Relative Clauses
Example: Children who (that) play with fire are in great danger of harm. The man who bought all the books by Hemingway has died.
Generally, who and which are more usual in written English whereas that is more usual in speech when referring to things.
Relative Pronouns Used As The Object of Defining Relative Clauses
Example: That`s the boy (ø , that, who, whom) I invited to the party. There`s the house (ø, that, which) I`d like to buy.
Relative Pronouns Used As A Possessive In A Defining Relative Clauses
Example: He`s the man whose car was stolen last week. They were sure to visit the town whose location (OR the location of which) was little known.
NOTE: It is preferable to use that (not which) after the following words: all, any(thing), every (thing), few, little, many, much, no(thing), none, some(thing), and after superlatives. When using the pronoun to refer to the object, that can be omitted.
Example: It was everything (that) he had ever wanted. There were only a few (that) really interested him.
Relative Pronouns Used As The Subject of Non-Defining Relative Clauses
Example: Frank Zappa, who was one of the most creative artists in rock `n roll, came from California. Olympia, whose name is taken from the Greek, is the capitol of Washington State.
Relative Pronouns Used As The Object of Non-Defining Relative Clauses
Example: Frank invited Janet, who (whom) he had met in Japan, to the party. Peter brought his favorite antique book, which he had found at a flee market, to show his friends.
NOTE That can never be used in non-defining clauses.
Relative Pronouns Used As A Possessive In Non-Defining Relative Clauses
Example: The singer, whose most recent recording has had much success, signing autographs. The artist, whose name he could not remember, was one of the best he had ever seen.
NOTES
In non-defining relative clauses, which can be used to refer to an entire clause.
Example: He came for the weekend wearing only some shorts and a t-shirt, which was a stupid thing to do.
After numbers and words like many, most, neither, and some, we use of before whom and