An apostrophe is a type of punctuation mark that can be used for a few different reasons.

Apostrophes can be used to:

• show ownership/possession
• form contractions
• indicate plurals 

A contraction is a shortened version of a word formed by merging words. The word ‘contract’ means to decrease in size or number.
Contractions are commonly used in speaking and writing.
We put an apostrophe to show where the letters are missing.

For example, I am can be shortened to I’m. The apostrophe is put in place of the missing letter a.
In everyday spoken English it is common to use contractions, so instead of saying “I am going to the park”, I would say “I’m going to the park”.

Another example is that I will can be shortened to I’ll. The apostrophe is put in place of the missing letters w and I.

There are formal and informal contractions. Formal contractions are used in both written and spoken English.
Informal contractions are used in spoken English in informal setting e.g. when talking to friends or family. Native English speakers often use informal contractions in everyday conversations.

Some common examples are:

• Are not ➜ aren’t
• I will ➜ I’ll
• It is ➜ It’s
• I have ➜ I’ve
• Is not ➜ Isn’t
• Do not ➜ Don’t
• Did not ➜ Didn’t
• You are ➜ You’re
• We are ➜ We’re

An apostrophe shows that something belongs to someone. There are several rules we need to learn. The rules depend on whether we are using a singular or plural noun.

Singular nouns refer to one person, place, thing, or idea. Some singular nouns end in the letter S, and some singular nouns don’t end in S.

Plural nouns refer to more than one person, place, thing, or idea. Some plural nouns end in the letter S and some plural nouns don’t end in S.

Singular nouns not ending in S

The rule for singular nouns not ending in S is to add an apostrophe followed by the letter S.

E.g. Lucy is a singular noun that does not end in the letter S. When talking about something that belongs to Lucy; then, we must place an apostrophe followed by the letter S. So, the correct sentence is ➜ Lucy’s glasses are pink. 

Singular nouns ending in S

The rule for singular nouns ending in S is to either add an apostrophe followed by the letter S or just an apostrophe. 

E.g. James is a singular noun that ends in S. When talking about something that belongs to James; then, we can show possession in two ways. The first way is to add an apostrophe followed by the letter S. The second way is to just add an apostrophe. 

➜ James’s bike is colourful.

➜ James’ bike is colourful. 

Plural nouns not ending in S

The rule for plural nouns not ending in S is to add an apostrophe followed by the letter S. 

E.g. Children is a plural noun that doesn’t end in S. When talking about something that belongs to the children; then, we must add an apostrophe followed by the letter S. 

➜ The children’s toys are new. 

Plural nouns ending in S

The rule for plural nouns ending in S is to add just an apostrophe. 

E.g. Parents is a plural noun ending in S. When talking about something that belongs to the parents; then, we must add just an apostrophe. 

➜ My parents’ house is big. 

Two or more people

The rule for two or more people is to add an apostrophe followed by the letter S.

E.g. Jim and Kim are two people. If we want to talk about something that belongs to them both; then, the rule is to add an apostrophe followed by the letter S after the second name. 

➜ Jim and Kim’s cat is cute. This indicates that they are joint owners of the cat.

If we want to talk about something that they are separate owners of; then, the rule is to add an apostrophe followed by the letter S after each name. 

➜ Jim’s and Kim’s cat is cute.

An apostrophe can indicate plurals. This is common with letters, numbers, and symbols.

For example, Cindy got three C‘s on her exams.