Parentheses, Brackets, and Ellipses

Learning Objectives

  • Demonstrate the proper use of parentheses, brackets, and ellipses

Parentheses

Appropriate alternative text for this image can be found in the caption.

Figure 1. A opening and closing parentheses.

Interestingly, parentheses can do more than make smiley faces :) and sad faces :( like these. Although they are quite handy for these important emoticons, they serve an important function in formal writing as well.

Parentheses are used to set off information in a sentence that is important but not really a part of the main message. It’s important to remember that your sentence should make sense if you eliminate the parentheses and all that is contained between them.

Other punctuation marks used alongside parentheses need to take into account their context. If the parentheses enclose a full sentence beginning with a capital letter, then the end punctuation for the sentence falls inside the parentheses. For example:

Typically, suppliers specify air to cloth ratios of 6:1 or higher. (However, ratios of 4:1 should be used for applications involving silica or feldspathic minerals.)

If the parentheses indicate a citation at the end of a sentence, then the sentence’s end punctuation comes after the parentheses are closed:

In a study comparing three different building types, respirable dust concentrations were significantly lower in the open-structure building (Hugh et al., 2005).

Finally, if the parentheses appear in the midst of a sentence (as in this example), then any necessary punctuation (such as the comma that appeared just a few words ago) is delayed until the parentheses are closed.

You can also use parentheses to provide acronyms (or full names for acronyms). For example, “We use the MLA (Modern Language Association) style guide here” or “The Modern Language Association (MLA) style guide is my favorite to use.”

Remember, parentheses always appear in pairs. If you open a parenthesis, you need another to close it!

Note: In technical writing, there are additional rules for using parentheses, which can be more nuanced. While we won’t discuss those rules here, it’s important to bear their existence in mind, especially if you’re considering going into a more technical field.

You’ll probably use parentheses most often in your research papers because both APA and MLA formatting require in-text citations using parentheses. So right after a quote or any other borrowed information, you should include an in-text citation in parentheses, as illustrated in these examples:

  • APA (Jones, 2011, p.131).
  • MLA (Jones 131).
Note that the period comes after the parenthesis in both APA and MLA format. The exception to this rule is with block quotes. When using block quotes, in both APA and MLA format, the period comes before the in-text citation.

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Brackets

Appropriate alternative text for this image can be found in the caption.

Figure 2. An opening and closing bracket.

Brackets are a fairly uncommon punctuation mark. Their main use is in quotations: they can be used to clarify quotes. For example, say you want to quote the following passage:

“I finally got to meet Trent today. I had a really great time with him. He was a lot taller than expected, though.”

However, you only want to relay the fact that Trent was taller than the speaker expected him to be. In order to do this, you would write the following: “[Trent] was a lot taller than expected.”

The brackets let the reader know that while the word Trent wasn’t in the original quote, his name was implied there. When using brackets, you need to be careful not to change the original meaning of the quote.

Another use of brackets is when there is a spelling or informational error in the original quote. For example, “Gabriel sat down on the river bank to fed [sic] the ducks.”  (The term sic means that the typo was in the original source of this quote.)

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Bracket Placement

See if you can correctly place the brackets in the following interactive.

Ellipses

Appropriate alternative text for this image can be found in the caption.

Figure 3. An ellipsis.

An ellipsis (plural ellipses) is a series of three periods, as you can see in the icon to the right.

As with most punctuation marks, there is some contention about its usage. The main point of contention is whether or not there should be a space between the periods (. . .) or not (…). MLA, APA, and Chicago, the most common style guides for students, support having spaces between the periods. Others you may encounter, such as in journalism, may not.

Quotes

Like the brackets we just learned about, you will primarily see ellipses used in quotes. They indicate a missing portion in a quote. Look at the following quote for an example:

Camarasaurus, with its more mechanically efficient skull, was capable of generating much stronger bite forces than Diplodocus. This suggests that Camarasaurus was capable of chomping through tougher plant material than Diplodocus, and was perhaps even capable of a greater degree of oral processing before digestion. This actually ties in nicely with previous hypotheses of different diets for each, which were based on apparent feeding heights and inferences made from wear marks on their fossilized teeth.

Diplodocus seems to have been well-adapted, despite its weaker skull, to a form of feeding known as branch stripping, where leaves are plucked from branches as the teeth are dragged along them. The increased flexibility of the neck of Diplodocus compared to other sauropods seems to support this too.

It’s a lengthy quote, and it contains more information than you want to include. Here’s how to cut it down:

Camarasaurus, with its more mechanically efficient skull, was capable of generating much stronger bite forces than Diplodocus. This suggests that Camarasaurus was capable of chomping through tougher plant material than Diplodocus. . . . This actually ties in nicely with previous hypotheses of different diets for each, which were based on apparent feeding heights and inferences made from wear marks on their fossilized teeth.

Diplodocus seems to have been well-adapted . . . to a form of feeding known as branch stripping, where leaves are plucked from branches as the teeth are dragged along them.

In the block quote above, you can see that the first ellipsis appears to have four dots. (“They are instantly recognized by their long, sweeping necks and whiplashed tails. . . .”) However, this is just a period followed by an ellipsis. This is because ellipses do not remove punctuation marks when the original punctuation still is in use; they are instead used in conjunction with original punctuation. This is true for all punctuation marks, including periods, commas, semi-colons, question marks, and exclamation points.

By looking at two sympatric species (those that lived together) from the fossil graveyards of the Late Jurassic of North America . . . , [David Button] tried to work out what the major dietary differences were between sauropod dinosaurs, based on their anatomy.

One of the best ways to check yourself is to take out the ellipsis. If the sentence or paragraph is still correctly punctuated, you’ve used the ellipsis correctly. (Just remember to put it back in!)

Try It

Quote the following passage, using ellipses to remove the bolded portions and using brackets for clarity where necessary.

Sauropod dinosaurs are the biggest animals to have ever walked on land. They are instantly recognized by their long, sweeping necks and whiplashed tails, and nearly always portrayed moving in herds, being stalked by hungry predators. In recent years, a huge amount of taxonomic effort from scientists has vastly increased the number of known species of sauropod. What we now know is that in many areas we had two or more species co-existing alongside each other. A question that arises from this, is how did we have animals that seem so similar, and with such high energy and dietary requirements, living alongside one another? Was there some sort of spinach-like super plant that gave them all Popeye-like physical boosts, or something more subtle?

This is a part of Martin Luther King’s famous “I Have a Dream” speech from the March on Washington for Jobs and Freedom in 1963. Quote part of the following passage, using ellipses to remove the bolded passage and making sure that you use the appropriate punctuation surrounding it:

 

I have a dream that one day on the red hills of Georgia, the sons of former slaves and the sons of former slave owners will be able to sit down together at the table of brotherhood. I have a dream that one day even the state of Mississippi, a state sweltering with the heat of injustice, sweltering with the heat of oppression, will be transformed into an oasis of freedom and justice. I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin but by the content of their character. I have a dream today. I have a dream that one day down in Alabama, with its vicious racists, with its governor having his lips dripping with the words of “interposition” and “nullification,”, one day right there in Alabama little black boys and black girls will be able to join hands with little white boys and white girls as sisters and brothers. I have a dream today.

 

 

The ellipsis can also indicate . . . a pause. This use is typically informal, and is only be used in casual correspondence (e.g., emails to friends, posts on social media, texting) or in literature. Because this use occurs in literature, you may find yourself quoting a passage that already has an ellipsis in it. For example, look at this passage spoken by Lady Bracknell, in The Importance of Being Ernest.

Well, I must say, Algernon, that I think it is high time that Mr. Bunbury made up his mind whether he was going to live or to die.  This shilly-shallying with the question is absurd.  Nor do I in any way approve of the modern sympathy with invalids.  I consider it morbid.  Illness of any kind is hardly a thing to be encouraged in others.  Health is the primary duty of life.  I am always telling that to your poor uncle, but he never seems to take much notice . . . as far as any improvement in his ailment goes.  I should be much obliged if you would ask Mr. Bunbury, from me, to be kind enough not to have a relapse on Saturday, for I rely on you to arrange my music for me.  It is my last reception, and one wants something that will encourage conversation, particularly at the end of the season when every one has practically said whatever they had to say, which, in most cases, was probably not much.

If you were to quote the passage, it may appear that something has been removed from the quote. So how can we indicate that this is not the case? If you think back to the bracket rules we just discussed, you may remember that [sic] can be used to show that an error was in the original. In a similar practice, we can enclose the ellipsis in brackets to show it appeared in the original work:

Well, I must say, Algernon, that I think it is high time that Mr. Bunbury made up his mind whether he was going to live or to die.  This shilly-shallying with the question is absurd.  Nor do I in any way approve of the modern sympathy with invalids.  I consider it morbid.  Illness of any kind is hardly a thing to be encouraged in others.  Health is the primary duty of life.  I am always telling that to your poor uncle, but he never seems to take much notice [. . .] as far as any improvement in his ailment goes.  I should be much obliged if you would ask Mr. Bunbury, from me, to be kind enough not to have a relapse on Saturday, for I rely on you to arrange my music for me.  It is my last reception, and one wants something that will encourage conversation, particularly at the end of the season when every one has practically said whatever they had to say, which, in most cases, was probably not much.

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