Are you uncertain about when to use an apostrophe? Many people have difficulty with this punctuation mark. The best way to get apostrophes right is to understand when and why they are used. There are two main cases – click on the links below to find straightforward guidance:
You use an apostrophe to show that a thing or person belongs or relates to someone or something: instead of saying the party of Ben or the weather of yesterday, you can write Ben’s party and yesterday’s weather.
Singular nouns and most personal names
We met at Ben’s party.
The dog’s tail wagged rapidly.
Yesterday’s weather was dreadful.
Personal names that end in –s
With personal names that end in -s: add an apostrophe plus s when you would naturally pronounce an extra s if you said the word out loud:
He joined Charles’s army in 1642.
Thomas's brother was injured in the accident.
Note that there are some exceptions to this rule, especially in names of places or organizations, for example:
St Thomas’ Hospital
If you aren’t sure about how to spell a name, look it up in an official place such as the organization’s website.
With personal names that end in -s but are not spoken with an extra s: just add an apostrophe after the -s:
The court dismissed Bridges' appeal.
Connors' finest performance was in 1991.
Plural nouns that end in –s
With a plural noun that already ends in -s: add an apostrophe after the s:
The work is due to start in two weeks’ time.
Plural nouns that do not end in -s
With a plural noun that doesn’t end in –s: add an apostrophe plus s:
The children’s father came round to see me.
He employs 14 people at his men’s clothing store.
The only cases in which you do not need an apostrophe to show belonging is in the group of words called possessive pronouns - these are the words his, hers, ours, yours, theirs (meaning ‘belonging to him, her, us, you, or them’) - and with the possessive determiners. These are the words his, hers, its, our, your, their (meaning 'belonging to or associated with him, her, it, us, you, or them'). See also it's or its?
An apostrophe can be used to show that letters or numbers have been omitted. Here are some examples of apostrophes that indicate missing letters:
I’m - short for I am
he’ll - short for he will
she’d – short for she had or she would
pick ’n’ mix - short for pick and mix
it’s hot - short for it is hot
didn’t - short for did not
It also shows that numbers have been omitted, especially in dates, e.g. the Berlin Wall came down in the autumn of ’89 (short for 1989).
These two words can cause a lot of confusion: many people are uncertain about whether or not to use an apostrophe. These are the rules to remember:
its (without an apostrophe) means ‘belonging to it’:
The dog wagged its tail.
Each case is judged on its own merits.
it’s (with an apostrophe) means ‘it is’ or ‘it has’:
It’s been a long day.
It’s cold outside.
It’s a comfortable car and it’s got some great gadgets.
The general rule is that you should not use an apostrophe to form the plurals of nouns, abbreviations, or dates made up of numbers: just add -s (or -es, if the noun in question forms its plural with -es). For example:
(e.g. The cost of the trip is 570 euros.)
(e.g. Traditional Italian pizzas are thin and crisp.)
(e.g. She buys big bags of organic apples and carrots.)
(e.g. Local MPs are divided on this issue.)
(e.g. The situation was different in the 1990s.)
It's very important to remember this grammatical rule.
There are one or two cases in which it is acceptable to use an apostrophe to form a plural, purely for the sake of clarity:
you can use an apostrophe to show the plurals of single letters:
I've dotted the i's and crossed the t's.
Find all the p's in appear.
you can use an apostrophe to show the plurals of single numbers:
Find all the number 7’s.
These are the only cases in which it is generally considered acceptable to use an apostrophe to form plurals: remember that an apostrophe should never be used to form the plural of ordinary nouns, names, abbreviations, or numerical dates.
You can read more rules and guidelines about apostrophes on the Oxford Dictionaries blog. Here you will find further examples of correct and incorrect use of apostrophes.
Back to punctuation.
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