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How to Use Apostrophes Correctly

November 14, 2023 | Blog, Learning Center

apostrophe

Apostrophes (’) may seem minor in the grand scheme of academic writing, yet their correct use is central to the writer’s respectability. At best, misusing an apostrophe will confuse your readers and dilute the effectiveness of your work. At worst, it will prompt your audience to stop taking you seriously altogether. Learning how to use apostrophes is critical to ensuring the professionalism of your academic work.

This comprehensive guide explains the ins and outs of how to use apostrophes correctly.

The basics of apostrophe use

Apostrophes serve two primary functions in English: indicating possession and forming contractions. While this seems straightforward enough, knowing exactly where to place an apostrophe can be challenging.

More complex rules governing edge cases often don’t make it into how-to guides and are therefore not widely understood, even by native English speakers.

1. Use apostrophes to indicate possession

Singular possession

For singular nouns and indefinite pronouns, add an apostrophe followed by an ‘s’ (e.g., the student’s book; anyone’s guess).

Plural possession

For plural nouns ending in ‘s’, add only an apostrophe (e.g., the students’ books). For plural nouns not ending in ‘s’, add an apostrophe and ‘s’ (e.g., children’s playground). Avoid errors like womens’ and childrens’.

Joint possession

Use an apostrophe on the final noun to show joint ownership (e.g., Alice and Bob’s research means that Alice and Bob are doing their research together).

Separate possession

Place apostrophes on both nouns to indicate separate ownership (e.g., Alice’s and Bob’s lab coats means that both Alice and Bob have lab coats – each person has their own).

2. Use apostrophes to form contractions and show elision

Contractions

Apostrophes are used to show omitted letters in contractions (e.g., do not becomes don’t). Academic writing tends to avoid contractions to maintain a formal tone, so use these sparingly, if at all.

Elision

When an apostrophe marks the omission of an initial or a final letter, the apostrophe is preceded or followed by a full space (e.g., rock ’n’ roll). When the apostrophe replaces a letter that appears mid-word, no space is used (e.g., ma’am).

3. Use apostrophes to form plurals (sometimes)

I know, I know – this runs counter to everything you’ve ever been told about apostrophes and plurals – but hear me out. In a few very clearly defined edge cases, we use apostrophes to create plurals because omitting them would create confusion. Let’s look at each of these cases in turn.

Plurals of lowercase letters

When lowercase letters must be referred to in plural form, apostrophes add clarity (e.g., when children first learn to write, they often confuse their b’s with their d’s).

Plurals of capital letters

For the same reason, we can add apostrophes to capital letters when referring to them as objects. This helps prevent miscues (e.g., she couldn’t tell whether the marks were A’s or arrows).

Plurals of lowercase abbreviations

When we refer to lowercase abbreviations in plural form, apostrophes help prevent miscues (e.g., academic writers sometimes have trouble telling their e.g.’s from their i.e.’s).

Plurals of capitalized abbreviations containing periods

When referring to the B.B.C.’s and the A.E.G.’s of the world in plural form, we use apostrophes. Omit the apostrophes, though, if your style guide calls for BBCs and AEGs without periods (British English tends to leave out the stops).

Plurals of symbols

When you’re in need of a plural symbol, use an apostrophe (e.g., she replaced all the &’s with “and”).  

Plurals of single-digit numerals

Single-digit numerals, when referred to as objects, can take apostrophes to aid clarity (e.g., find all the 6’s in that pile of number tiles).

Common apostrophe mistakes

  • Its vs. It’s: ‘Its’ indicates possession (e.g., the cat licked its paw), while ‘it’s’ is a contraction for ‘it is’ or ‘it has’ (e.g., it’s been a long day).
  • Plurals vs. Possessives: With the exception of the edge cases discussed above, don’t use apostrophes to form plurals (we eat apples rather than apple’s and listened to Duran Duran in the 1980s rather than the 1980’s).
  • Possessive Pronouns: Pronouns like hers, yours, ours, theirs, whose, and its are possessive but do not require apostrophes.
  • Spans of Time: In expressions of spans of time, use an apostrophe after the unit of time: a few weeks’ holiday, two days’ grace. If you can replace the apostrophe with the word of, then you can use an apostrophe in the phrase (two weeks of holidaytwo weeks’ holiday).
  • Compound Nouns and Noun Phrases: Place the apostrophe after the final noun in the compound noun or noun phrase (e.g. my brother-in-law’s horses; student nurses’ schedules).
  • Double Possessives: Both of and the apostrophe s are used with nouns and pronouns relating to people or with personal names (e.g., that car of her sister’s caused more trouble than it was worth; he was a friend of Robert’s).
  • Residences and Places of Business: I’m visiting the hairdresser’s; I’m at Aveleigh’s.
  • Singular Names Ending in ‘S’: It’s customary to add an apostrophe s to singular names that end in s (e.g., Dickens’s novels).
  • Biblical Names: Jesus’ is an accepted archaic form; in non-liturgical contexts, prefer Jesus’s.
  • Classical Names: Style guides differ on this point. New Hart’s Rules notes that, conventionally, an apostrophe alone is used after classical names ending in s or es: Socrates’ death, Euripides’ tragedies. For shorter names, the apostrophe s is permissible: Zeus’s revenge. The Chicago Manual of Style advises using the apostrophe s in classical names of two or more syllables even though we wouldn’t pronounce the additional s: Euripedes’s tragedies. Either form is fine; just be consistent throughout the text.
  • French Names: Use an apostrophe s after names that end in a silent s, x or z when used possessively: Descartes’s theories, Camus’s novels.
  • Plurals of Surnames: When visiting your neighbours, Mary Jones and Bryce Jones, you are visiting the Joneses, not the Jones’s or the Jones’.
  • Possessives of Plural Surnames: If your neighbours supplied you with a particularly wonderful meal, you might later tell a friend about the dinner you enjoyed at the Joneses’.

What editors need to know about using apostrophes correctly

When Microsoft Word tries to “help”

You might occasionally be called on to write something like the ’90s, where the apostrophe precedes the balance of the text. Microsoft Word will autocorrect the apostrophe to an opening quotation mark, leaving you with the ‘90s. The apostrophe is now facing the wrong way and is therefore no longer an apostrophe at all. Spotting and correcting this kind of thing puts you in the 99th percentile of editors – an editing ninja.

Word processors also don’t distinguish between apostrophes and single closing quotation marks. When a word ends in an apostrophe, no period or comma should intervene between the word and the apostrophe. Be mindful of this when running global find and replace actions, for instance to change a document from British punctuation style to American punctuation style.

Italicised names

When a singular or plural name or term is italicised, set the possessive apostrophe s that follows in roman text: the Telegraph’s chief editor; the Titanic’s maiden voyage.

When abbreviations become possessive

Avoid forming the possessive of an abbreviation that is followed by a spelled-out form in parentheses (or vice versa). Write the long history of NASA (the National Aeronautical and Space Administration), not NASA’s (the National Aeronautical and Space Administration’s) long history.

Established Businesses

The names of many large businesses originally ended in possessive apostrophes that have, over time, disappeared. These are now written as though they were plurals (e.g., Macys, Harrods, Barclays Bank, Publishers Weekly). Other institutions (e.g., Levi’s) have retained their apostrophes. Never change a consistently applied style without checking with the author. Always check whether the names of places or organizations that end in s ought to have an apostrophe. It’s impossible to tell without consulting the New Oxford Dictionary for Writers or Editors, the institution’s own website, or a gazetteer or encyclopedic dictionary, as there’s no real rhyme or reason here.

Abbreviations Functioning as Verbs

The board has OK’d our proposal.

For … sake expressions

These expressions receive apostrophes, or not, according to euphony. Thus, we have for goodness’ sake but for expedience’s sake.

 

Apostrophes, tiny as they are, play an outsize role in clear and respectable writing. When in doubt, consult a reputable style guide or seek advice from an experienced editor. Our editors can provide clarity on obscure rules and ensure that your writing stands out for the right reasons.

Sources

Anne Waddingham | New Hart’s Rules: The Oxford Style Guide

Bryan A. Garner | The Chicago Guide to Grammar, Usage, and Punctuation

Chicago University Press | The Chicago Manual of Style, 17th Edition

Grammarbook | Apostrophes

Oxford University Press | New Oxford Dictionary for Writers and Editors

Want to learn more about academic writing? Learn how to use abbreviations in academic writing.

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