The Possessive Apostrophe: Singular, Plural, and the Tricky Exceptions

Master the possessive apostrophe with clear rules for singular, plural, and irregular nouns — plus common mistakes and exam-focused practice.

May 17, 2026 Updated on May 17, 2026 Punctuation , Writing Skills 6 min read

The apostrophe is tiny, but getting it wrong can change meaning entirely.

The girl**‘s** bag — one girl owns the bag.
The girls**’** bags — multiple girls own multiple bags.

One letter’s difference in placement changes everything. And then there is the classic trap: its (possessive) vs it’s (it is). This article gives you the complete rule set — singular, plural, irregular, and the exceptions that confuse even experienced writers.

Rule box: Singular nouns: add ‘s. Regular plurals ending in s: add ’ (just the apostrophe). Irregular plurals not ending in s: add ‘s.

Noun Type	Rule	Example
Singular	+ ‘s	the girl‘s bag, James‘s car
Regular plural (ends in s)	+ ‘	the girls’ bags, the teachers’ room
Irregular plural (no s)	+ ‘s	the children‘s toys, the men‘s coats

For any singular noun, add ‘s regardless of the final letter.

The boy**‘s** bicycle
The boss**‘s** decision
James**‘s** book (or James’ book — both accepted; see note below)
The bus**‘s** wheels

Note on names ending in s: Both James’s and James’ are accepted in modern usage. James’s is more common in American English and in most modern style guides (APA, Chicago). James’ is traditional British usage. Pick one style and stay consistent.

If the plural already ends in s, add only an apostrophe after it.

The girls**’** bags (multiple girls)
The teachers**’** room (multiple teachers)
The dogs**’** leashes
Two weeks**’** notice

Irregular plurals like children, men, women, people, mice do not end in s. Treat them like singular nouns — add ‘s.

The children**‘s** toys
The men**‘s** department
The women**‘s** team
The people**‘s** choice
The mice**‘s** tails

For compound nouns, add the apostrophe to the last word.

My mother-in-law**‘s** recipe
The attorney general**‘s** statement
The passer-by**‘s** comment

Joint possession (two people own one thing together): Add ‘s to the last name only.

Rahul and Priya**‘s** house (they share one house)

Separate possession (each owns their own): Add ‘s to each name.

Rahul**‘s** and Priya**‘s** houses (each has their own house)

It’s = it is / it has
Its = possessive (belonging to it)

It’s raining. (it is)
The dog wagged its tail. (possessive)

This is one of the most common errors in English. Remember: it’s always means it is or it has. If you can substitute it is, use it’s. Otherwise, use its.

Is the noun singular? → Add ‘s.
Is the noun a regular plural ending in s? → Add just ’.
Is the noun an irregular plural (not ending in s)? → Add ‘s.
Is it a compound noun? → Add ‘s to the last word.
Is it joint or separate possession? → Joint: last name only. Separate: each name.
Is it its/it’s? → Can you replace with “it is”? Use it’s. Otherwise, its.

The girl**‘s** bag was stolen. (singular)
The girls**’** bags were stolen. (regular plural)
The children**‘s** toys are new. (irregular plural)
James**‘s** car is red. (singular name ending in s)
The teachers**’** room is on the first floor. (regular plural)
The men**‘s** coats were hanging by the door. (irregular plural)
My mother-in-law**‘s** recipe is secret. (compound noun)
Rahul and Priya**‘s** house is large. (joint possession)
It’s time to go. (it is)
The cat licked its paw. (possessive)

❌ The girl bag was stolen.
✅ The girl**‘s** bag was stolen.

Without the apostrophe, girl is just a noun, not a possessive.

❌ The childrens**’** toys.
✅ The children**‘s** toys.

Children is already plural. Never add s to make it plural. Just add ‘s for possession.

❌ The dog wagged it’s tail.
✅ The dog wagged its tail.

It’s = it is. You would not say “the dog wagged it is tail.”

❌ Apple**‘**s for sale.
✅ Apples for sale.

Never use an apostrophe to make a regular plural. Apostrophes show possession, not plurality.

The 1990**‘s** music. → Acceptable but old-fashioned.
The 1990s music. → Preferred in modern usage.
Three MP**‘s** were present. → Acceptable but increasingly rare.
Three MPs were present. → Modern preference.

For decades and acronyms, the trend is to drop the apostrophe in plurals.

Wrong	Right	Why
The girls bag.	The girl‘s bag.	Singular possessive needs ‘s.
Childrens toys.	The children‘s toys.	Irregular plural — add ‘s.
The dog wagged it’s tail.	The dog wagged its tail.	Its = possessive.
Apple’s for sale.	Apples for sale.	No apostrophe in plurals.

Choose the correct option or spot the error.

The ___ room is on the second floor. (teacher’s / teachers’)
___ going to rain. (Its / It’s)
The ___ toys are broken. (children’s / childrens’)
Error spotting: The boy’s bicycle’s wheel is bent.
Error spotting: The womens team won the match.
Error spotting: Its a beautiful day.
Fill in the blank: My sister___ house is nearby. (‘s / ’)
Fill in the blank: The two brothers___ rooms are separate. (‘s / ’)
Rewrite correctly: The childrens books are on the table.
Choose: Rahul and Priya___ car is new. (‘s / ‘)

teachers’ — plural possessive (multiple teachers).
It’s — it is going to rain.
children’s — irregular plural, add ‘s.
The boy’s bicycle wheel is bent. — no need for apostrophe on “wheel.”
The women’s team won the match. — irregular plural women + ‘s.
It’s a beautiful day. — it is.
’s — singular possessive (one sister).
’s — separate possession, each brother has his own room.
The children’s books are on the table. — irregular plural + ‘s.
‘s — joint possession (one car shared).

Rule: Singular → ‘s. Regular plural (ends in s) → just ’. Irregular plural → ‘s. Its = possessive. It’s = it is.

Memory trick: “Possessive apostrophes show ownership. Its never splits — it owns. It’s always means it is.”

Revise these:

The girl**‘s** bag (singular)
The girls**’** bags (regular plural)
The children**’** toys (irregular plural)
The dog wagged its tail (possessive)
It’s raining (it is)

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