The rules concerning the use of apostrophes in written English are very simple:
They are used to denote a missing letter or letters, for example:
I can’t instead of I cannot
I don’t instead of I do not
it’s instead of it is or it has
They are used to denote possession, for example:
the dog’s bone
the company’s logo
Jones’s bakery (but Joneses' bakery if owned by more than one Jones)
This applies to all nouns, so the correct versions are Jesus’s disciples, Keats’s poems and so on.
Please note that “Its”, which is usually used as a possessive adjective (like “our”, “his” etc), does not take an apostrophe:
the dog ate its bone and we ate our dinner
however, if there are two or more dogs, companies or Joneses in our example, the apostrophe comes after the 's':
the dogs' bones
the companies' logos
- Apostrophes are NEVER ever used to denote plurals! Common examples of such abuse (all seen in real life!) are:
Banana’s for sale which of course should read Bananas for sale
Menu’s printed to order which should read Menus printed to order
MOT’s at this garage which should read MOTs at this garage
1000’s of bargains here! which should read 1000s of bargains here!
New CD’s just in! which should read New CDs just in!
Buy your Xmas tree’s here! which should read Buy your Xmas trees here!
Note: Special care must be taken over the use of “your” and “you're” as they sound the same but are used quite differently:
your is possessive as in this is your pen
you're is short for “you are” as in you’re coming over to my house
The Chairman of the Apostrophe Protection Society, John Richards, has received many enquiries regarding the correct use of the apostrophe in the English language. Below are some of the Frequently Asked Questions he has answered:
Can an inanimate object own something?
When considering the use of an apostrophe, possession involves of and for. Consider a notice outside a golf club: Captain’s parking space. The captain doesn’t own the space; it is a parking space for the captain.
In the case of this car’s colour is too bright the car doesn’t own the colour; it is the colour of the car.
Another example is men’s clothing or men’s wear. It is clothing for men.
Where should the apostrophe go if a word ends in an ‘s’ ?
The ending of the word is irrelevant. The general agreement is that the singular possessive is indicated by ‘s and we say this applies however the word ends. Thus it should be James’s book, not James’ book, which is a plural possessive.
What if there are several people called James who share the book?
The plural of James is Jameses and plural possession is denoted by s’ so it should be this is the Jameses’ book.
Should apostrophes be used after numbers or single letters?
Many people write I had four A’s in my exam or mind your p’s and q’s. We would say that the apostrophe is meaningless in these cases. I had four As and I will mind my ps and qs is perfectly clear and could hardly be misunderstood and no apostrophes have been misused.
If something is owned by, or relates to, two people where does the apostrophe go?
It generally goes on the second name as in John and Mary’s wedding or Bill and Sonia’s house. It would go on both only if it were not common to them, as in John’s and Mary’s houses were well designed.