(1) My little dog is three years old.

(2) He is half Maltese and half Yorkie.

• Sentences (1) and (2) are grammatically correct.

• They are so short, however, that you may wish to combine them.

(3) My little dog, who is half Maltese and half Yorkie, is three years old.

• Sentence (3) is a combination of (1) and (2).

• Who has replaced he, the subject of sentence (2). Who introduces the rest of the idea, is half Maltese and half Yorkie.

• Who is called a relative pronoun because it relates "is half Maltese and half Yorkie "to my little dog."

• BE CAREFUL: An idea introduced by a relative pronoun cannot stand alone as a complete and independent sentence. It is dependent: it needs an independent idea ( like "My dog is three years old) to complete its meaning.

More Examples

(4) Michael gives great art lessons.

(5) All his students love them.

(6) Michael gives great art lessons, which all his students love.

 

(7) I have a large living room.

(8) It can hold many people.

(9) I have a large living room that can hold many people.

• As you can see, which and that also can be used as relative pronouns.

• In sentence (6) what does which relate or refer to?

• When who, which, and that are used as relative pronouns, they usually come directly after the word they refer to.

My little dog, who. . .

. . . art lessons, which. . .

. . . living room that. . .

• BE CAREFUL: Who, which, and that cannot be used interchangeably.

Who refers to people.

Which refers to things.

That refers to people or things.

Punctuating Ideas Introduced by WHO, WHICH, or THAT

Ideas introduced by relative pronouns can be one of two types, either restrictive or nonrestrictive. Punctuating them must be done carefully.

RESTRICTIVE

Never eat mushrooms that are found in the wild.

• The relative clause in this sentence is "that are found in the wild."

• Can you leave out that are found in the wild and still keep the basic meaning of the sentence?

• No! You are not saying don't eat mushrooms, but don't eat certain kinds of mushrooms--wild ones.

• Therefore, that are found in the wild is restrictive; it restricts the meaning of the sentence.

A restrictive clause is not set off by commas; it is necessary to the meaning of the sentence.

NONRESTRICTIVE

My laptop, which is a Toshiba, was given to me by my husband.

• The relative clause in this sentence is "which is a Toshiba."

• Can you leave out which is a Toshiba and still keep the basic meaning of the sentence?

• Yes! Which is a Toshiba merely adds a fact. It does not change the basic idea of the sentence that my laptop was given to me by my husband.

• Therefore, which is a Toshiba is called  nonrestrictive because it does not restrict or change the meaning of the sentence.

A nonrestrictive clause is set off by commas; it is not necessary to the meaning of the sentence.

Note: Which is often used as a nonrestrictive relative pronoun.

Resource:

Fawcett, Susan and Alvin Sandberg. Grassroots: The Writer's Workbook Fourth

      Edition. Boston: Houghton Mifflin, 1991.