What is apostrophes in English grammar?

Apostrophes is an important concept in English grammar. This lesson explains the rules, formation, and usage with clear examples to help you master it.

How do I use apostrophes correctly?

To use apostrophes correctly, follow the rules explained in this lesson. Pay attention to the examples and practice with the quiz at the end of the page.

What are common mistakes with apostrophes?

Common mistakes include incorrect formation and usage in context. Review the examples in this lesson to avoid these errors in your writing and speaking.

Punctuation

Apostrophes

Quick Summary

The apostrophe (') has two primary functions: showing possession (John's book) and indicating contractions (don't, it's). Despite being a small punctuation mark, apostrophe errors are among the most common in English writing.

The apostrophe is a small punctuation mark with significant responsibilities in English. While it may seem straightforward, apostrophe misuse is one of the most common grammatical errors-appearing on shop signs, in professional documents, and throughout the internet. Understanding when to use (and when NOT to use) apostrophes is essential for clear, correct writing.

1. Apostrophes for Possession (Showing Ownership)

The possessive form shows that something belongs to someone or something else. The rules differ based on whether the noun is singular, plural, or ends in "s."

Singular Nouns: Add 's (apostrophe + s)

the dog's bone (the bone belonging to the dog)
Sarah's computer (the computer belonging to Sarah)
the company's policy (the policy of the company)
my boss's decision (the decision of my boss)
the child's toy (the toy belonging to the child)

Plural Nouns Ending in -s: Add only an apostrophe (s')

the dogs' bones (bones belonging to multiple dogs)
the students' textbooks (textbooks belonging to the students)
the teachers' lounge (the lounge for the teachers)
my parents' house (the house belonging to my parents)
the companies' merger (merger between the companies)

Plural Nouns NOT Ending in -s: Add 's (apostrophe + s)

the children's toys (toys belonging to the children)
the women's bathroom (bathroom for women)
the people's choice (the choice of the people)
the men's department (department for men)
the mice's cage (cage of the mice)

2. Special Cases for Possession

Singular Nouns Ending in -s:

For singular nouns already ending in "s," you can add either 's or just an apostrophe. Both are acceptable, but consistency is key:

James's car OR James' car
the boss's office OR the boss' office
Charles's book OR Charles' book
the witness's testimony OR the witness' testimony

Joint vs. Individual Possession:

Jack and Jill's bucket (they share ONE bucket), apostrophe on last name only
Jack's and Jill's buckets (each has their OWN bucket), apostrophe on both names
Mom and Dad's car (one car they share)
Mom's and Dad's cars (separate cars)

Compound Nouns:

my mother-in-law's advice
the attorney general's ruling
somebody else's problem
the commander-in-chief's orders

Time Expressions:

Use apostrophes with time periods to show possession:

a day's work (the work of one day)
two weeks' notice (notice of two weeks)
a year's supply (supply for a year)
three hours' delay (a delay of three hours)
today's meeting (the meeting of today)

3. Apostrophes in Contractions

A contraction combines two words into one, with an apostrophe marking where letters have been removed. Contractions are common in spoken English and informal writing but may be avoided in very formal contexts.

Common Contractions:

Contraction	Full Form	Example
I'm	I am	I'm going to the store.
don't	do not	I don't understand.
can't	cannot	She can't come today.
won't	will not	He won't be late.
you're	you are	You're doing great!
they're	they are	They're arriving soon.
it's	it is / it has	It's raining. / It's been fun.
we've	we have	We've finished the project.
shouldn't	should not	You shouldn't worry.
let's	let us	Let's go for a walk.

4. The Most Confusing Apostrophe Pairs

⚠️ It's vs. Its, The #1 Apostrophe Mistake

it's = contraction of "it is" or "it has"

its = possessive pronoun (like his, her, their)

Test: Replace with "it is." If it makes sense, use "it's." If not, use "its."

• "The dog wagged its tail." (The dog wagged it is tail? NO → "its")

• "It's raining outside." (It is raining outside? YES → "it's")

Other Commonly Confused Pairs:

you're vs. your: "You're" = you are. "Your" = possessive. "You're going to love your new car."
they're vs. their vs. there: "They're" = they are. "Their" = possessive. "There" = location. "They're going to their house over there."
who's vs. whose: "Who's" = who is/has. "Whose" = possessive. "Who's the person whose car is blocking the driveway?"
we're vs. were vs. where: "We're" = we are. "Were" = past tense of "be." "Where" = location.

5. When NOT to Use Apostrophes

❌ Common Apostrophe Errors (The "Grocer's Apostrophe")

NEVER use apostrophes to form regular plurals!

WRONG: "Apple's for sale" → CORRECT: "Apples for sale"
WRONG: "The Smith's live here" → CORRECT: "The Smiths live here"
WRONG: "Video's available" → CORRECT: "Videos available"
WRONG: "The 1990's" → CORRECT: "The 1990s"
WRONG: "Two DVD's" → CORRECT: "Two DVDs"

More Rules for When NOT to Use Apostrophes:

Possessive pronouns NEVER take apostrophes: his, hers, its, ours, yours, theirs, whose
Plural abbreviations usually don't need apostrophes: "CEOs," "PhDs," "FAQs" (though some style guides accept "FAQ's")
Decades: "the 1980s" NOT "the 1980's" (though the apostrophe version was once common)
Family names in plural: "The Johnsons" NOT "The Johnson's" (unless showing possession: "The Johnsons' house")

6. Special Uses of Apostrophes

Omitted Numbers:

the '90s (the 1990s)
class of '22 (class of 2022)
the spirit of '76 (1776)

Omitted Letters in Dialect or Casual Speech:

rock 'n' roll
'cause (because)
singin' and dancin'
y'all (you all)

Plurals of Single Letters (for clarity):

To avoid confusion, apostrophes are sometimes used when pluralizing single letters:

Mind your p's and q's.
She got all A's on her report card.
Dot your i's and cross your t's.

Practice: Spot the Errors

Can you find the apostrophe errors in these sentences?

"The dog wagged it's tail happily." (Should be: its)
"Fresh tomato's for sale!" (Should be: tomatoes)
"Your going to love this movie." (Should be: You're)
"The childrens' playground needs repair." (Should be: children's)
"Whose coming to the party?" (Should be: Who's)

Frequently Asked Questions

Should I write "James's" or "James'"?

Both are correct. Traditional rule: Add 's (James's). Modern alternative: Add just an apostrophe (James'). The key is consistency throughout your document. Chicago Manual of Style prefers "James's" while AP Style prefers "James'".

Is it "1990s" or "1990's"?

Modern style guides recommend "1990s" without an apostrophe. The apostrophe version ("1990's") is considered outdated, though you might still see it in older texts.

How do I make "it" possessive?

"Its" (no apostrophe) is possessive. "It's" (with apostrophe) always means "it is" or "it has." This is confusing because normally possessives have apostrophes, but possessive pronouns (his, hers, its, whose, theirs) never do.

What about possessives with inanimate objects?

While "of" phrases are sometimes preferred for inanimate objects (the leg of the table), apostrophes are widely accepted: "the table's leg," "the building's entrance," "the car's engine." Both forms are grammatically correct.

Test Your Knowledge

Apostrophes Quiz

Question 1 of 3

Which sentence shows correct possession for a singular noun?

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