TIP Sheet
PARENTHESES

Parentheses are used to enclose incidental or supplemental information or comments. The parenthetical information or comment may serve to clarify or illustrate, or it may just offer a digression or afterthought. Parentheses are also used to enclose certain numbers or letters in an outline or list.

1. Use parentheses to enclose additional or supplemental information that clarifies or illustrates a point.

In a business letter the salutation and body of the letter are flush left (against the left margin).

Everything that went wrong that day (the accident, the missed appointment, the argument) was eventually forgotten in the midst of the joyful celebration.

2. Use parentheses to offer a digression or afterthought.

The mayor should apologize for his angry outburst (so typical for someone caught in a lie) at the meeting last night.

Your use of citations in the last paper (which was beautifully written, by the way) offered a good example of how to avoid plagiarism.

3. Use parentheses to enclose numbers or letters introducing items in a list or outline.

There are five steps to cleaning an aquarium: (a) Put the fish somewhere else; (b) drain the water out; (c) scrub the inside of the glass; (d) add dechlorinated fresh water; and (e) return the fish.

4. Punctuate parenthetical material according to the following guidelines:

• A statement (as opposed to a question or exclamation) that is contained within parentheses inside another sentence does not begin with a capital letter or end with a period, even if it can stand alone as its own complete sentence.

His family's arrival (they had never called us) was a surprise.

• However, if the enclosed sentence forms a complete question or exclamation, then you may punctuate it as a complete sentence, beginning with a capital letter and ending with a question mark or exclamation point.

I am certain we saw a ghost (Have you ever seen one?) on the stairs that night.
We were all frightened (My husband was terrified!) by the image we saw.

• Punctuation which applies to the surrounding sentence is placed outside the parentheses.

Should I invite him by telephone (very politely, of course)?
When Frances sat down next to Ducky (her cat), she was very careful not to sit on her tail.

• If a parenthetical enclosure contains a complete sentence and it stands alone (not within another surrounding sentence, but between sentences), then punctuation appropriate to that sentence is placed inside the parentheses.

For years, his brother desperately wanted that car. (He finally gave it to him!) It was a 1948 Buick in mint condition.

Note: Refer to the TIP Sheets on "The Comma," "The Hyphen," and "The Dash, Slash, Brackets, and Ellipsis" to help you differentiate among the uses of parentheses and these other various punctuation marks.