Belonging to: In the simplest of terms, the apostrophe is used to identify ownership or belonging to [someone or something].

First identify the victim's fingerprints from inside the suspect's car.

The protesters' voices were drowned out by the sound of the gunfire.

The children's laughter filled the theatre.

What if the item belongs to a person? ...and what if the name of the person ends with an ~s already? Add an apostrophe ~s to the end of the name as shown in these examples:

The wind blew Clementine's hat off.

Although it was James's cat, it spent most of its time at Charles's house.

For animals and things that end in ~s, you can just add an apostrophe like this:

All of the bus's windows had been blown out.

The octopus' legs had wrapped around the man's entire body.

Physical things

Apostrophes used to mean 'the [something] of [something else]':
Notice that the examples so far have been about physical things. But the same grammar applies to abstract ideas or academic concepts too.

He suggests that luck's relevance to morality is only in the evidence it provides of what judgement a 'moral agent' deserves.

Existential intelligence is a skill concerned with an individual's ability to analyze life's meaning and issues of human existence.

A comparison is provided here between modern democracies and the democracies of Plato's time.

This is fun! Try the BBC's apostrophe game: Who owns what game (not touchscreen friendly).

Possessive adjectives

Possessive adjectives - his, her, their, my, your, its, our

Words such as his, her, my ... are words which already suggest that something belongs to someone (or something) and so do not need an apostrophe:

The pick-pocket placed his hand inside the pocket of the coat that Julie was wearing and drew out her keys.

They pooled together their money and bought her house.

Note: One / One's
One should always mind one's manners when in polite company.

Pls English Users YouTube channel - Apostrophes video thumbnail

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