Interruptions generally get a bad rap. But the renowned physician and writer Buwei Yang Chao once asked, “Have you ever noticed that life consists mostly of interruptions, with occasional spells of rush work in between?”1 Just a few years earlier, C.S. Lewis pointed out, “The truth is, of course, that what one regards as interruptions are precisely one's life.”2
If interruptions are the stuff of life, then parenthetical elements, which are written interruptions, must also carry some significance.
Parenthetical Element Definition
The parenthetical element of a sentence is information that is not necessary to the meaning of that sentence. Parenthetical elements are what we might call an interruption or an aside. It's information that’s unessential but adds extra details or liveliness to the sentence.
Based on the name, you might be tempted to think parenthetical elements should always be set off by parentheses, but that’s not the case. You can separate these interjections with either commas, parentheses, or dashes.
Fig. 1 Parenthetical elements are a disruption to the progression of a thought, or sentence
A parenthetical element could be a word or a phrase, but it interrupts the flow of a sentence with supplemental information. Parenthetical elements must be nonrestrictive.
A nonrestrictive element is one that offers extra information about the subject or an object in a sentence that is not essential to its meaning. In other words, you can remove the parenthetical element without altering the meaning of the sentence. The phrase “in other words” from the previous sentence is an example of a nonrestrictive element.
See how the parenthetical element operates in the following sentences:
The novel, the first of its kind, was poorly received in its time.
The novel, which happened to be written by a woman, was poorly received in its time.
The novel, requiring years of the author’s life, was poorly received in its time.
The novel, including the sequel that followed, was poorly received in its time.
The novel, after years of trying to be published, was poorly received in its time.
The parenthetical information is highlighted in each example above, and even placed in the same position in each case, to show the variety of parenthetical information. Regardless of the additional information, the meaning of the sentence never changes.
Although the above examples show the parenthetical details in the middle of the sentence, nonrestrictive information can appear anywhere in a sentence—the beginning, middle, or end. No matter their placement, they are almost always set apart by some kind of punctuation.
Punctuation is the use of marks or symbols inserted in a sentence or phrase to clarify meaning.
Using a Comma with Parenthetical Elements
The most common way to add parenthetical information to a sentence is to close it in between two commas (as seen in the examples above). You’ll see this method used most often because writers use commas to separate parenthetical elements that are the least disruptive to the sentence.
The type of punctuation used to separate a parenthetical idea depends on the degree of the interruption caused by that information.
Commas are Used for Least Interruption
The president’s State of the Union address was encouraging, even if a little lengthy, and I’m glad I listened to it.
This example shows how commas encase a parenthetical element that is only slightly disruptive to the sentence. It gives details about the length of the President’s speech, but it doesn’t interrupt the flow of the sentence to any great extent.
When a parenthetical word or phrase is at the beginning of a sentence, it is followed by a comma. If it is at the end of a sentence, it’s preceded by a comma.
Parentheses are Used for More Interruption
William Shakespeare wrote over 150 poems (both short and long).
The parentheses in this example separate some information that adds insight but aren’t highly disruptive to the sentence. The same information could have used commas instead, but the author has control over the message and how to convey it. The parentheses indicate a more disruptive thought.
Dashes are Used for Most Interruption
A thesaurus is one of the few books—no, it’s the only book—a college study really needs.
This example uses em dashes to set apart the parenthetical thought. Em dashes differ from en dashes and hyphens in that they are longer—the length of the capital letter M. Using dashes this way draws attention to the information between the dashes and really breaks up the flow of the sentence. Use dashes when you want to embrace the disruption of the sentence.
Types of Parenthetical Elements
There are eight types of parenthetical elements that you can add to a sentence. Each of these types serves a particular purpose.
Introductory Phrase
Introductory phrases introduce something helpful to the meaning of the sentence but don't contain a subject and a verb.
Running out of time, the soldiers mounted the hilltop.
Interjection
An interjection is a word or phrase that communicates sudden or vivid emotion through sound, or simply a “yes” or “no.”
I would love a ride to the library, yes.
Mmm, that smells delightful!
Aside
An aside is a comment that isn’t related to the subject. Often a sarcastic remark.
I am, as you can imagine, very upset about the grade my teacher gave me.
Appositive
An appositive is a noun or noun phrase, placed beside another noun or noun phrase, that serves to further identify the first noun or phrase.
My hero, Martin Luther King Jr., fought to the death for equality in the United States.
Absolute Phrase
This is a noun or pronoun and a participle phrase that modifies the entire sentence. These allow for the movement of the description of the entire person, place, or thing to a specific aspect or detail.
The professor stood in front of the class, hands grasping the podium.
Free Modifier
Free modifiers come in several forms. Generally, it's a phrase or clause that modifies the main clause (or another free modifier) by giving more information about the subject.
The building remained intact, reflecting the passing clouds in its windows.
Summative Modifier
True to their name, summative modifiers summarize the main clause of a sentence. These are modifiers, usually noun phrases, that appear at the end of the sentence.
He finally faced his fear of heights—a crippling obstacle that had kept him from too many fun things in his life.
Resumptive modifier
Similar to summative modifiers in that it appears at the end of a sentence, but instead of summarizing, a resumptive modifier resumes a sentence where it left off by repeating a word or phrase.
She hit the ball hard, a hit that could be heard on the other side of the park.
The Importance of Parenthetical Elements
You might think of parenthetical information as details that just pop into your head and disrupt the main thought. This is sometimes the case, but parenthetical elements are often highly valuable to the reader.
Writers use parenthetical elements to add extra information to their writing, which provides helpful insights for the audience. Whether you’re writing a personal letter or an academic essay, an “aside” here and there can add color and additional layers of meaning to your message.
Fig. 2 - There are countless examples of parenthetical elements in fiction and non-fiction writing.
When analyzing a text, look at the author’s use of parenthetical elements, especially in fictional writing. Authors tend to hide important details about characters and settings in places that aren’t, grammatically speaking, important to the objective of a sentence. Pay close attention to how information hides inside sentences; you might miss significant details by skimming over parenthetical information.
A word of caution as a writer: it is possible to overuse parenthetical elements. You might feel tempted to add lots of extra information to your sentences, but they can easily become bogged down by too much detail. This will be distracting to your readers.
More Parenthetical Element Examples
The following are examples of parenthetical elements found in literature.
The following quote comes from Elizabeth Gaskell’s North and South (1854) as Mrs. Thornton discusses the love life of her son, John Thornton.
And what proof more would you have, I wonder, of her caring for you? (Ch. 23)
This simple parenthetical element is set apart by commas because it doesn’t deviate far from the rest of the sentence. It’s a simple aside that doesn’t add much to the sentence in general.
The next example is found in Mansfield Park (1814) by Jane Austen. In this passage, Fanny’s Uncle, Sir Thomas, is confronting her about her interactions with Mr. Crawford.
You must have observed his attentions; and though you always receive them very properly, (I have no accusation to make on that head,) I never perceived them to be unpleasant to you. (Vol. III, Ch. 1)
This is an unusual example because Austen added double punctuation for Sir Thomas’s aside; you’ll notice she set commas and parentheses around the comment. This is perhaps because she wanted to add extra emphasis to this part of the sentence. In her mind, it’s possible that the character is heavily emphasizing the statement to sound insistent about his notion of Fanny’s propriety. Or it could just be an element of grammar from a bygone era.
The final example is from Flannery O’Connor’s short story, Everything That Rises Must Converge (1963).
There was no bus in sight. Julian, his hands still jammed in his pockets and his head thrust forward, scowled down the empty street.
This is an example of an absolute phrase. Julian, the subject of the sentence, is described in greater detail through this additional phrase. Why does Flannery O’Connor find this important enough to add? Although the details don’t change the meaning of the sentence, they do give the reader great insight into Julian’s demeanor. Knowing how he’s holding himself gives the reader a hint about how he’s feeling, and so for this reason, this aside information is highly relevant to the audience.
Parenthetical Element - Key Takeaways
- The parenthetical element of a sentence is information that is not necessary to the meaning of that sentence.
- Parenthetical elements must be nonrestrictive.
- The most common way to add parenthetical information to a sentence is to close it in between two commas, but you can also use em dashes and parentheses.
- The type of punctuation used to separate a parenthetical idea depends on the degree of the interruption caused by that information.
- There are eight types of parenthetical elements that you can add to a sentence.
- Aside
- Summative modifier
- Resumptive modifer
- Absolute phrase
- Free modifier
- Appositive
- Interjection
- Introductory phrase
Buwei Yang Chao, Autobiography of a Chinese Woman, 1947.
C.S. Lewis, They Stand Together: The Letters of C.S. Lewis to Authur Greeves (1914-1963), 1979.
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