How to Use a Comma Correctly with an Appositive
An appositive is a word or phrase that refers to the same thing as another noun in the same sentence. It is placed beside another noun or pronoun to explain or identify it.
Applying commas correctly with an appositive can be tricky. A comma is needed for clarifying information that is not essential to understanding the noun, and commas are not needed if the clarifying information is essential.
Therefore, if you could remove the appositive without changing the meaning of the sentence, it is a nonessential appositive and should be set off with commas. If the appositive is necessary, it is an essential appositive, and it should not be set off with commas.
A mnemonic trick I use to remember this grammar rule is:
- appositive could be removed = nonessential = comma needed (nonessential, needed)
- appositive is necessary = essential = comma excluded (essential, exclude)
- My sister, Frances, founded the company.
- The painter, one of the city’s most promising young artists, began showing his work in galleries before he was sixteen.
- Chocolate, my favorite treat, always makes me happy.
- The venerated New York Times reported publishing revenue was down by 18% last year.
- My assistant Carrie will call you tomorrow to resolve this problem.
- Our colleague Bryan is ill.