Apostrophe: Definition, Rules And Examples In English

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Apostrophes can be tricky for beginners, but they are essential for showing possession and certain contractions. Let’s discuss where and how to use them correctly with simple rules.

What is an Apostrophe?

An apostrophe is a punctuation mark used to indicate possession or omitted letters in contractions.

Examples:
John’s (possession)
It’s (contraction for “it is”)
Children’s (possession)
They’re (contraction for “they are”)
Boss’s (possession)

How to Use an Apostrophe for Possession

With Singular Possessors:

When a singular noun owns something, place the apostrophe before the s.

The cat’s toy (The toy belongs to the cat).

With Plural Possessors:

For plural nouns that end in s, place the apostrophe after the s.

The dogs’ bowls (The bowls belong to the dogs).

For Plural Nouns Not Ending in S:

When the plural form of a noun does not end in s, place the apostrophe before the s.

The children’s books (The books belong to the children).

For Singular Nouns Ending in S:

With singular nouns ending in s, the apostrophe can be placed before or after the s, depending on style preference.

The boss’s car or The boss’ car.

For Compound Nouns:

Place the apostrophe at the end of the entire compound noun to show possession.
My brother-in-law’s house (The house belongs to my brother-in-law).

Joint vs. Individual Ownership:

For joint ownership, use one apostrophe after the second possessor.
Tom and Jerry’s apartment (The apartment belongs to both Tom and Jerry).

For individual ownership, each possessor needs their own apostrophe.
Tom’s and Jerry’s cars (Tom owns a car, and Jerry owns a car).

Apostrophe for Possession vs. Contraction

Apostrophes serve two main functions in English: showing possession and replacing missing letters in contractions. Understanding the difference between these uses is crucial for clear writing, especially when certain words look similar but have different meanings depending on whether they include an apostrophe.

Possession:

When the apostrophe is used to show possession, it indicates ownership.

Contractions:

In contractions, the apostrophe replaces missing letters. For example, it’s is short for it is, where the apostrophe takes the place of the missing letter i.

It’s raining outside (contraction)

It’s is a contraction of it is. The apostrophe replaces the missing i in is.

It is raining outside.

The dog wagged its tail (possession without apostrophe)

Its shows possession (something belongs to it). This is one of the few possessive forms in English that does not use an apostrophe.

The tail belongs to the dog.

They’re going to the park (contraction)

They’re is a contraction of they are, with the apostrophe replacing a.

They are going to the park.

Their house is on the corner (possession)

Their shows possession, indicating that the house belongs to them. Unlike they’re, no apostrophe is used because it’s not a contraction.

The house belongs to them.

John’s car is parked outside (possession)

John’s shows possession, meaning the car belongs to John. Here, the apostrophe is placed before the s to show ownership.

The car belongs to John.

Key Tip:

It’s = It is or It has (contraction)
Its = Possessive form (shows ownership)
They’re = They are (contraction)
Their = Possessive form (shows ownership)
John’s = Possessive form (shows ownership)

Rules To Follow

Apostrophes can sometimes be confusing, especially with singular and plural possessors or compound nouns. Let’s break down each rule with clear explanations and multiple examples to eliminate any confusion.

Singular Possessors: Apostrophe before “s”

When a singular noun owns something, we place the apostrophe before the s to show possession.

The girl’s bicycle
The apostrophe before the s indicates that the bicycle belongs to the girl (one girl).

The teacher’s book
The book belongs to one teacher. The apostrophe comes before the s to show possession by a singular noun (teacher).

Plural Possessors Ending in “s”: Apostrophe after “s”

For plural nouns that end in s, the apostrophe goes after the s to show that the possession belongs to more than one person or thing.

The students’ classroom
The apostrophe comes after the s because the classroom belongs to multiple students.

The dogs’ toys
There are many dogs, and the toys belong to all of them. The apostrophe goes after the s in dogs to indicate plural possession.

Plural Nouns Not Ending in “s”: Apostrophe before “s”

For plural nouns that do not end in s (irregular plurals), place the apostrophe before the s to show possession.

The children’s playground

The word children is already plural, and it doesn’t end in s, so the apostrophe goes before the s to indicate that the playground belongs to the children.

The men’s jackets

The jackets belong to multiple men. Since men is a plural noun that doesn’t end in s, the apostrophe is placed before the s to show possession.

Singular Nouns Ending in “s”: Apostrophe Placement Varies

When singular nouns end in s, you can either place the apostrophe before or after the s, depending on style preference. Both forms are generally acceptable, but consistency is key.

The boss’s office

Here, the apostrophe and s are both added after the singular noun boss to show possession. This is common when you pronounce the extra s sound.

The boss’ office

Alternatively, you can place the apostrophe after the s without adding another s. Both forms indicate that the office belongs to the boss.

Compound Nouns: Apostrophe at the End of the Compound

When using compound nouns to show possession, place the apostrophe at the end of the entire compound noun.

My mother-in-law’s recipe

The recipe belongs to my mother-in-law. The apostrophe is placed at the end of the entire compound noun mother-in-law.

The editor-in-chief’s decision

The decision belongs to the editor-in-chief. The apostrophe is placed after the entire compound noun editor-in-chief.

Final Overview of Rules

Apostrophe before s
(The boy’s book).

Plural possessors ending in “s”:
Apostrophe after s (The girls’ school).

Plural nouns not ending in “s”:
Apostrophe before s (The women’s team).

Singular nouns ending in “s”:
Apostrophe placement varies (The boss’s car or The boss’ car).

Compound nouns:
Apostrophe at the end of the compound (My brother-in-law’s car).

Example Sentences with Apostrophe

The dog’s leash is hanging by the door.
My sister’s birthday is next week.
The students’ homework was submitted on time.
The teacher’s lounge is on the second floor.
The women’s soccer team won the championship.
The cat’s toys are scattered around the room.
My parents’ house is always warm in winter.
The children’s laughter filled the park.
The boss’s meeting is scheduled for 3 PM.
The editor-in-chief’s article was well-received.

Common Mistakes:

Misplacing the apostrophe:

✗ The cats toy (Missing apostrophe).
✓ The cat’s toy.

Confusing plural and possessive forms:

✗ The girls are playing with they’re toys (Incorrect contraction and no possession).
✓ The girls are playing with their toys.

Using apostrophes for non-possessive plurals:

✗ The dog’s are barking (Apostrophe is not needed for plural dogs).
✓ The dogs are barking.

Using apostrophes with possessive pronouns:

✗ That book is her’s. (Incorrect use of apostrophe with possessive pronoun)
✓ That book is hers. (Possessive pronouns do not need apostrophes)

Omitting the apostrophe in contractions:

✗ Its raining outside. (Missing apostrophe in the contraction)
✓ It’s raining outside. (The apostrophe replaces the missing letter in “it is”)

Misplacing the apostrophe in plural possessives:

✗ The childrens’ toys are scattered. (Apostrophe incorrectly placed after the s for an irregular plural)
✓ The children’s toys are scattered. (Apostrophe before the s for irregular plural possessive)