Apostrophe Rules: Complete Guide

Quick Answer

Use apostrophes for:

Contractions: don't, can't, it's (it is)
Singular possession: Sarah's book, the dog's tail
Plural possession: students' grades, the teachers' lounge

Never use apostrophes for: Regular plurals (bananas, CDs, 1990s)

Memory Trick: Apostrophes show missing letters or ownership—never regular plurals.

🔑 Key Takeaway

Apostrophes show missing letters (contractions) or ownership (possession). They NEVER make regular words plural. "Apple's for sale" is always wrong—it's "Apples for sale."

Quick Comparison

Focus	What to Check	Why It Matters
Main rule	Apostrophe Rules: Complete Guide	Start with the quick answer before applying the rule in a sentence.
Final check	Compare the sentence against the examples on this page.	This helps you avoid choosing a form or rule too early.

Common Mistakes

❌ Incorrect:

Applying apostrophe rules: complete guide without checking what the sentence is doing.

✓ Correct:

Use the quick answer first, then confirm the rule with the examples on this page.

Use apostrophes for: Never use apostrophes for: Regular plurals (bananas, CDs, 1990s)

🎯 Test Your Knowledge

1. What should you check first when applying Apostrophe Rules: Complete Guide?

Answer: Use apostrophes for: Never use apostrophes for: Regular plurals (bananas, CDs, 1990s)

Frequently Asked Questions

What should I remember about Apostrophe Rules?

Use apostrophes for: Contractions: don't, can't, it's (it is) Singular possession: Sarah's book, the dog's tail Plural possession: students' grades, the teachers' lounge Never use apostrophes for: Regular plurals (bananas, CDs, 1990s)

What quick test helps me with Apostrophe Rules?

Apostrophes show missing letters or ownership—never regular plurals.

What should I check before using Apostrophe Rules?

Apostrophes show missing letters (contractions) or ownership (possession). They NEVER make regular words plural. "Apple's for sale" is always wrong—it's "Apples for sale."

Word Origins & Etymology

Apostrophe comes from Greek 'apostrophos' (accent of turning away), from 'apostrephein' (to turn away). Originally a mark showing omitted letters, it gained a possessive function in English during the 17th century.

English uses apostrophes for two purposes: (1) contractions (don't = do not) and (2) possession (John's book). The confusion arises because possessive pronouns (its, yours, theirs) break the possessive rule by NOT using apostrophes.

🔗 The Connection

The apostrophe is statistically the most misused punctuation mark in English, primarily because of the its/it's confusion and the 'grocer's apostrophe' (apple's for sale).

Real-World Examples

See how these words work in genuine contexts — from business emails to academic papers.

📏 Contraction:

Don't forget to submit the report. (do not)

Apostrophe replaces omitted letters

📏 Possession:

Sarah's presentation was excellent.

Apostrophe + s = belonging to Sarah

📏 Plural Possession:

The students' grades were posted. (multiple students)

Apostrophe after the 's' for plural nouns

⚠️ Irregular Plural:

The children's playground needs repair.

Irregular plurals (children, women, men) add 's — not s'

⚠️ Pronouns:

The dog wagged its tail. (NO apostrophe)

Possessive pronouns NEVER take apostrophes: its, yours, hers, theirs

❌ Grocer's Apostrophe:

Fresh apple's for sale!

Wrong: plural nouns NEVER take apostrophes. It's 'apples' (plural), not 'apple's' (possessive).

❌ Common Mistake:

The Jones's are coming to dinner.

Wrong: for plural family names, add -es with no apostrophe: 'The Joneses.' Use apostrophe only for possession: 'the Joneses' house.'

❌ Common Mistake:

The 1990's were a great decade.

Debatable: AP style says '1990s' (no apostrophe for decades). Some style guides accept '1990's.'

💡 Three Rules:

1. Contractions: apostrophe replaces letters. 2. Possession: 's for singular, s' for plural. 3. Pronouns: NEVER use apostrophes (its, yours, theirs).

These three rules cover 99% of apostrophe usage

💡 The Test:

If you can expand it (it's → it is), it's a contraction → apostrophe. If it shows ownership and isn't a pronoun → apostrophe. Otherwise → no apostrophe.

This decision tree resolves nearly all apostrophe questions

Why Do People Confuse Them?

Apostrophes serve two unrelated functions (contraction AND possession), and then break their own possession rule for pronouns. This triple inconsistency makes them the hardest punctuation mark to master. The 'grocer's apostrophe' (using apostrophes in simple plurals like 'banana's') is so common it became a named phenomenon.

For more practice, review Its vs It's and Subject-Verb Agreement.

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Apostrophe Rules: The Complete Guide