What Is an Apostrophe? (Punctuation)
Taught in US schools
Key Takeaways
- Apostrophes have two jobs: showing possession and forming contractions.
- For contractions, the apostrophe replaces missing letters (do not → don't).
- For possession, add 's to singular nouns and ' to plural nouns ending in -s.
- Apostrophes are NEVER used to make a noun plural - this is a very common error.
What Is an Apostrophe?
An apostrophe ( ' ) is a punctuation mark with two specific jobs in English:
- Forming contractions - replacing missing letters when two words are joined
- Showing possession - indicating that something belongs to someone or something
Despite being one of the most common punctuation marks, apostrophes are also one of the most frequently misused. Understanding the two rules clearly is the key to using apostrophes correctly.
Apostrophes in Contractions
A contraction combines two words into one by leaving out one or more letters. The apostrophe marks the spot where letters were removed.
do not: don't - o
it is: it's - i
they are: they're - a
I am: I'm - a
could not: couldn't - o
Common confusion: it's (contraction for "it is") vs. its (possessive pronoun, no apostrophe). When in doubt, try reading the sentence with "it is" - if it sounds right, use it's.
Apostrophes for Possession
To show that something belongs to a noun, use an apostrophe.
Singular nouns - add 's:
- the student's backpack (one student)
- Maria's pencil
- the dog's leash
Plural nouns ending in -s - add only the apostrophe:
- the students' backpacks (more than one student)
- the teachers' lounge
- the dogs' bowls
Plural nouns NOT ending in -s - add 's:
- children's books
- women's team
- mice's nest
The #1 Apostrophe Error: Plurals
Apostrophes never make a word plural. This is one of the most common writing errors.
-
❌ I have three cat's.
-
✅ I have three cats.
-
❌ The apple's are on the table.
-
✅ The apples are on the table.
If you want more than one of something, just add -s or -es. No apostrophe needed.
Practice Activities
- Sort a list of words with apostrophes into two columns: "Contraction" and "Possession."
- Write five sentences about things belonging to classmates: "Jayla's notebook," "Marcus's eraser."
- Edit a paragraph that contains intentional apostrophe errors - students find and correct each mistake.
- Play "Contraction Bingo" - call out two-word phrases, students mark the contraction on their card.
Frequently Asked Questions
What does an apostrophe do?
An apostrophe (') has two main uses: (1) forming contractions by replacing omitted letters (cannot → can't), and (2) showing possession (the dog's bowl, the teacher's desk). It is not used to make words plural.
How do you use an apostrophe for possession?
For a singular noun, add apostrophe + s: the cat's tail, James's book. For a plural noun that ends in -s, add just the apostrophe: the teachers' lounge, the dogs' bowls. For a plural noun that does NOT end in -s (children, men), add apostrophe + s: children's books, men's coats.
What is the most common apostrophe mistake?
The most common mistake is using an apostrophe to make a word plural. For example, writing 'apple's for sale' or 'I have two dog's.' Apostrophes never make words plural. To make a word plural, just add -s or -es with no apostrophe.
Free Apostrophe (Punctuation) Worksheets
Curriculum-aligned printable worksheets for 2nd – 5th Grade. Download free.
Common Core Standards
