Definition: Parentheses ( ) enclose information and separate it from the main idea of the sentence or paragraph. They should be used only when necessary. It's better in formal writing to rewrite sentences to avoid using parentheses and brackets.
- Parenthesis is the singular form of parentheses, but these marks are always used in pairs.
Use parentheses to set off ideas that function as asides in a sentence or paragraph. Parenthetical information can be removed without altering the meaning of a sentence or paragraph. Parentheses are used in many situations:
Boudicca led the Iceni (an independent British people) against the Romans.
We had erdbeerkuchen (strawberry cake) for dessert.
My dog (an Akita) is the smallest of the giant breeds.
We set up our tent (we pretended we were in the wilderness) in the backyard.
Talking to the reader
Joshua served a souffle that he had made himself. It was awful (but don't tell him I said that).
Punctuation with Parentheses
Punctuation with parentheses is very similar to punctuation with quotation marks.
Parenthetical sentence at the end of a sentence
If the information in the parentheses is a separate, complete sentence, the period at the end of the sentence goes inside the parentheses.
We spent two hours at the zoo. (Most of us could have spent two hours watching the otters.)
Notice how the first sentence ended before the parenthetical expression started. This means that the sentence inside the parentheses must start with a capital letter.
Parenthetical phrase at the end of a sentence
If you use a phrase (in other words, an incomplete sentence) in parentheses at the end of a sentence, the period goes outside the parentheses.
We ordered three pepperoni pizzas (my favorite).
Parenthetical sentence in the middle of a sentence
A complete parenthetical sentence in the middle of a sentence does not require a period. The first letter of the parenthetical sentence is not capitalized because it is in the middle of the main sentence, not after it.
Our two hour final (it was our longest exam) included a three page essay.
- Parenthetical sentence at the end of a sentence
Commas generally go outside the parentheses.
The drought continued (64 days and counting), and many farmers' crops were destroyed.
Question marks and exclamation marks
If the parenthetical comment itself is an exclamation or question, the exclamation or question mark goes inside the parentheses.
Ana got a 100 (the only one in the class!) on her test. It was her 12th perfect score in a row. (Can you imagine?)
Conventions with Parentheses
Numbers or letters in a list
Make sure you include (1) your cover sheet, (2) your essay, and (3) your bibliography.
Their hours are from 8 AM (EST) to 5 PM (EST).
His phone number is (321) 555-5555.
Beginning and end dates
William Shakespeare (1564-1616) wrote 38 plays.
The Hundred Years' War (1337-1453) actually lasted longer than one hundred years.
Definition: Brackets [ ] separate and enclose information. They are used less frequently than parentheses and are most often used in relation to quotations.
Brackets with Quotations
Use brackets to enclose words that you have added or changed in a quotation. Also use brackets for explanations within a quotation.
Danny's note read, "Thomas and Lucas left their homework at my house [italics added]."
The newspaper reported, "The enemies were captured, and [they] were imprisoned."
The teacher explained, "This test [the one they had taken the day before] showed that you really understood the material."
In the third example, the author—not the teacher—is explaining that the test was the day before.
Using [sic] in a Quotation
Use [sic] to show that an error in a quotation is from the original source.
Jennifer wrote, "My pupy [sic] is named Joe."