An apostrophe (’) is used to create possessive forms, contractions and some plural forms. It indicates where the letter has been omitted.
I am = I’m
He’s = he is
They’re = they are
Do not = don’t
I’d = I would or I had
She would have failed. = She would’ve failed.
Contracted forms are not considered appropriate in formal writing. However, it is basically a matter of personal choice.
Before writing contractions in a paper that is going to be graded, you should ask your tutor whether it is appropriate to include them in your writing.
Apostrophes are used in writing possessives.
While writing possessives, the position of the apostrophe depends on whether the noun is singular or plural.
If the noun is singular, the apostrophe goes before the –s. Example: the girl’s parents
If the noun is plural, the apostrophe usually goes after the –s. Example: the girls’ parents
If the plural form of the noun does not end in –s, the apostrophe goes before the –s. Example: the men’s hostel
You can also create possessive forms with of. In this case, no apostrophes are used.
- A friend of mine works abroad.
Common mistakes
The words its and it’s are often confused.
Its is a possessive word.
- The dog wagged its tail.
It’s means it is or it has.
- It’s your book. (= It is your book.)
- It’s stopped raining. (= It has stopped raining.)
They’re and their
These two expressions are also confused.
They’re means they are. Their is a possessive word.
They took their children along.
- They’re waiting for us. (= They are waiting for us.)
‘There are’ does not have an appropriate contracted form.
An apostrophe is also used to form the plurals of letters and digits. This is particularly common when the letters are written in the small case.
- Mind your p’s and q’s.
- She got 4 a’s this term.
Apostrophes are no longer used to form plurals of years.
- Example: 1990s (more natural than 1990’s)