The Apostrophe’s What?
Apostrophes are used to show that something is missing. That’s it. No magic, nothing difficult, no reason to worry: their job is to mark a gap. They are never, ever used for plurals.
If you read, He went to speak to the dog’s, you would – and should – ask, the dog’s what? That’s how you know it’s wrong: if you can ask what? and expect an answer – the dog’s owner – then it’s not a plural, it’s a possessive. If the man went to speak to the dogs, you wouldn’t be prompted to ask what. That, which, who – you could add all of those and more, but not what.
The woodsman cut down the tree’s. The tree’s what? What part of the tree? The woodsman cut down the trees.
Keeping up with the Jones’s. The Jones’s what? Their speed-walking butler? Keeping up with the Joneses.
They are used when to be, to have and to do are shortened. We’ve grown lazy; we join the verb to the pronoun and knock out a bit from the middle for speed.
I’m, he’s, she’s – that’s elision: shunting two words together and losing a little in the process. When we speak, context explains what’s intended; on the page, the apostrophe has been invented to do the job.
It’s – ‘it is’ or ‘it has’. How do you know which is referred to? It’s in the context. It’s correct – it is correct; it’s been done correctly – it has been done correctly.
That’s, there’s – never used for that was, there was.
They’re, we’re, you’re – They are, we are, you are. Again, not used for they were, we were, you were.
I’ve, we’ve, you’ve – I have, we have, you have.
I’d, we’d, I didn’t, he hadn’t, we wouldn’t – you get the picture.
I’d could be I had, I would – I’d have had the fish if I’d known the soup would be so bad. You’d have done the same.
To recap: if you’re squashing two words into one, something has got to go – otherwise why bother? – and the apostrophe is the symbol that marks the gap and the change in sound that results.
2. They signify possessives.
The dog’s dinner. The cat’s pyjamas— the dinner of the dog, the pyjamas of the cat. What’s missing is ‘of the’, and the thing that is possessed has been moved from before the owner to after it. The sentence is shorter as a result, which is the whole point.
It doesn’t matter whether the object being possessed is singular or plural: it’s the owner’s number that governs the apostrophe.
If there were multiple dogs and cats, the apostrophe would move along a little.
The dogs’ dinner was put in their bowl; the cats’ pyjamas were stripy: the dinner of the dogs, the pyjamas of the cats. You don’t add another ‘s’ after the apostrophe: we don’t say the dogs’s dinner.
The dogs’ dinners were put in their bowls – the dinners of the dogs. The cats’ pyjamas – doesn’t change, because pyjamas is a plural noun (though the cats’ pyjama trousers).
The child’s toys – the toys of the child.
The children’s toys – the toys of the children. It would be wrong to write ‘the childrens’ toys, because you wouldn’t say the toys of the childrens. What happens before the apostrophe has to be able to stand as a word in its own right. The children’s rocking horse – the rocking horse that is shared by the various children.
The woman’s car – the car of/belonging to the woman.
The women’s car – the car of the women.
The women’s cars – the cars of the women.
2A (for Anomalies)
Its own right: here is a possessive that doesn’t take an apostrophe; if it did, it would be the same as it’s, which it isn’t. The same applies to hers, ours, yours and theirs – these possessive pronouns have come to be complete on their own.
3 Individually and collectively
The sister and brother’s cats; the sister’s and brother’s cats. The first says that the cats belong to both the sister and the brother; the second says that the sister and the brother each have cats, but they’re not under shared ownership.
The sisters’ and brothers’ cats – the cats belonging to the sisters and the cats belonging to the brothers; the sisters and brothers’ cats – the cats belonging jointly to the sisters and brothers.
My sister’s cat’s pyjamas — the pyjamas of the cat owned by my sister.
Shakespeare’s comedies; Chaucer’s and Shakespeare’s comedies – not Chaucer and Shakespeare’s comedies, because they didn’t co-write them; they didn’t share ownership.
The King’s daughter, but the King of Spain’s daughter – the first is the daughter of the King, the second specifically the daughter of the King of Spain.
If the singular noun ends in s, it’s pretty much up to your ear to say how you use the apostrophe:
Rabies’ effects are disastrous, not rabies’s effects.
The scissors’ handles, not the scissors’s handles, nor the scissor’s handles
The bus’s brakes didn’t work – you would say it, so punctuate it that way.
Apostrophes crop up in other places too.
Let’s – an elision of let us in common speech.
Can’t, didn’t, won’t, wouldn’t – contraction of cannot, did not, will not, would not.
One o’clock – one of the clock, an archaic way of telling the time which we still use but without knowing it, because the contraction has replaced the original phrase and become the norm.
He OD’d on heroine. When an abbreviation is being used as a verb, you don’t write he ODed, or OD’ed, which would sound wrong if you pronounced it: odeeded. You’d say he odeed – so OD’d.
6. To recap: Never use it in a plural: and if you see one, ask it what it’s doing there.