P6-b: Dash, parentheses, brackets
The dash
When typing, use two hyphens to form a dash (--). Do not put spaces before or after the dash. If your word processing program has what is known as an “em-dash” (—), you may use it instead, with no space before or after it.
Use a dash to set off parenthetical material that deserves emphasis.
One of music’s rising trends—lyrics that promote the use of synthetic drugs—is leading some artists to speak out against their peers.
Use a dash to set off appositives that contain commas. An appositive is a noun or noun phrase that renames a nearby noun. Ordinarily most appositives are set off with commas (P1-e), but when the appositive itself contains commas, a pair of dashes helps readers see the relative importance of all the pauses.
In my hometown, people’s basic needs—food, clothing, and shelter—are less costly than in a big city like Los Angeles.
A dash can also be used to introduce a list, a restatement, an amplification, or a dramatic shift in tone or thought.
Along the wall are the bulk liquids—sesame seed oil, honey, safflower oil, and that half-liquid “peanuts only” peanut butter.
In his last semester, Peter tried to pay more attention to his priorities—applying to graduate school and getting financial aid.
Everywhere we looked there were little kids—a bag of Skittles in one hand and their mommy or daddy’s sleeve in the other.
Kiere took a few steps back, came running full speed, kicked a mighty kick—and missed the ball.
In the first two examples, the writer could also use a colon. (See P3-d.) The colon is more formal than the dash and not quite as dramatic.
tip: Unless there is a specific reason for using the dash, avoid it. Unnecessary dashes create a choppy effect.
Parentheses
Use parentheses to enclose supplemental material, minor digressions, and afterthoughts.
Nurses record patients’ vital signs (temperature, pulse, and blood pressure) several times a day.
Use parentheses to enclose letters or numbers labeling items in a series.
Regulations stipulated that only the following equipment could be used on the survival mission: (1) a knife, (2) thirty feet of parachute line, (3) a book of matches, (4) two ponchos, (5) an E tool, and (6) a signal flare.
tip: Rough drafts are likely to contain unnecessary parentheses. As writers head into a sentence, they often think of additional details, using parentheses to work them in as best they can. Such sentences usually can be revised to add the details without parentheses.
Brackets
Use brackets to enclose any words or phrases that you have inserted into an otherwise word-for-word quotation.
Audubon reports that “if there are not enough young to balance deaths, the end of the species [California condor] is inevitable” (4).
The sentence quoted from the Audubon article did not contain the words California condor (since the context of the full article made clear what species was meant), so the writer needed to add the name in brackets.
The Latin word “sic” in brackets indicates that an error in a quoted sentence appears in the original source.
According to the review, Nelly Furtado’s performance was brilliant, “exceding [sic] the expectations of even her most loyal fans.”
Do not overuse “sic,” however, since calling attention to others’ mistakes can appear snobbish. The preceding quotation, for example, might have been paraphrased instead: According to the review, even Nelly Furtado’s most loyal fans were surprised by the brilliance of her performance.
note: For advice on using “sic” in MLA, APA, and CMS styles, see MLA-3a, APA-3, and CMS-3, respectively.