Parentheses
Parentheses are punctuation marks, represented by a pair of rounded vertical lines ( ), used to enclose information that adds to but is not essential for understanding a sentence. This enclosed information can include words, phrases, complete sentences, or references to source material. Parentheses can also clarify lists, such as when items are numbered, and they serve to provide definitions for abbreviations and acronyms upon their first mention. The term "parenthesis" originates from Greek, meaning "beside-in-put," and the marks themselves emerged during the Renaissance period in the 1500s. While considered less formal than other punctuation options like commas or colons, parentheses enhance written communication by allowing authors to interject additional thoughts or clarifications without disrupting the main flow of the text. Proper usage of parentheses involves certain punctuation rules, such as placing end punctuation inside the parentheses for complete sentences and outside for incomplete ones. Overall, parentheses are a versatile tool in writing that aids in providing context and clarification.
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Parentheses
Parentheses are punctuation marks used to set off information that enhances a sentence but is not necessary to understand it. This information can be a single word, a phrase, a complete sentence, or a reference to source material. Parentheses are also used to surround numbers to add clarity to a list of items and to abbreviations. In many instances, they are considered less formal than commas, colons, and semicolons and may be replaced with those forms of punctuation. However, they can still be useful and add interest and information to written works.
The word parenthesis, referring to one half of a parentheses pair, comes from the Greek words para, en, and thesis. It translates roughly to “beside-in-put” and originally referred to a statement or thought interjected into writing or a conversation. Parentheses appeared as punctuation marks in the 1500s during the Renaissance and went by several other names; the most notable of these was lunulae, a name coined by sixteenth-century Dutch Christian humanist Desiderius Erasmus. He called them that because the vertical curved lines reminded him of a lunar crescent, or crescent moon.
Overview
Parentheses are a pair of vertical lines that are rounded and curve toward each other at top and bottom ( ). A single such line is called a parenthesis; this term is also sometimes used to refer to the information enclosed in parentheses. Parentheses are always used in pairs as punctuation.
Parentheses are used to enclose information that relates to a sentence but is not essential to understanding it. For instance, “My favorite notebook (the blue one) is full.” It is important to be sure the sentence can be understood even if the information in parentheses is omitted. For example, “Her favorite holidays are Thanksgiving (and Christmas)” would be incorrect. They can also be used to set apart the author’s thoughts in a narrative, as in “The store sold farm-fresh milk, ice cream, and other items. (Their milkshakes were my favorite!)” Using parentheses in this way requires the author to follow additional punctuation rules as well. If the material in the parentheses is a complete sentence, the end punctuation goes inside the final parenthesis. If it is not a complete sentence, punctuation goes outside. Commas are used after a parenthesis, not before.
Another use for parentheses is to add reference information to a sentence. This is also known as an in-text citation. For example, “The population rate has grown significantly in the past ten years (see Table 2).” This usage also applies to references to other materials, including books, periodicals, and websites.
Parentheses are also used to help clarify information in the text. For instance, they can be used with numbered lists, as in “She is traveling to (1) New York, (2) Florida, and (3) California.” They are additionally used to provide information about abbreviations and acronyms the first time they appear in a document, such as “He ran ten kilometers (km) in the race to benefit the American Diabetes Association (ADA).” Parentheses enclose area codes in phone numbers and surround date ranges related to people and events, as in “Abraham Lincoln (1809–1865) was president during the American Civil War (1861–1865).”
Bibliography
Ellis, Matt. “Parentheses vs. Brackets: Definitions and Examples.” Grammarly, 15 Nov. 2022, www.grammarly.com/blog/parentheses-and-brackets/. Accessed 11 Nov. 2023.
Ferguson, Ashleigh. “Parenthesis vs Parentheses: What’s the Difference?” ProWritingAid, 13 Oct. 2022, prowritingaid.com/parenthesis-vs-parentheses. Accessed 11 Nov. 2023.
“June and the Parenthesis.” English Project, www.englishproject.org/june-and-parenthesis. Accessed 11 Nov. 2023.
“Parentheses.” Butte College, www.butte.edu/departments/cas/tipsheets/punctuation/parentheses.html. Accessed 11 Nov. 2023.
“Parentheses.” Northern Illinois University Effective Writing Practices Tutorial, www.niu.edu/writingtutorial/punctuation/parentheses.shtml. Accessed 11 Nov. 2023.
“Parentheses.” Punctuation Guide, www.thepunctuationguide.com/parentheses.html. Accessed 11 Nov. 2023.
“Parentheses.” University of Texas at San Antonio Writing Center, www.utsa.edu/twc/documents/Parentheses.pdf. Accessed Nov. 11, 2023.
“What Are Parentheses and How Do You Use Them?” Thesaurus.com, 18 March 2022, www.thesaurus.com/e/grammar/parentheses/. Accessed 11 Nov. 2023.