Using apostrophes correctly

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Apostrophes can be used to replace missing letters, to show possession (including terms like three months' wages) and, occasionally, to show plurals.

When to Use Apostrophes

The rules about when to use apostrophes can be summarised:

a. To replace missing letters (e.g., aren't).
b. To show possession (e.g., Sarah's jumper).
c. In expressions such as 3 months' wages.
d. In the plurals of abbreviations, letters and numbers (e.g., 6's and 7's).

Unless it is covered by one of the categories above, an apostrophe should not be used.

The Most Common Mistake with Apostrophes

Words that end in the letter s seem to attract apostrophes. The plural of words ending in vowels (e.g., video, patio) are extremely prone to this error.

Hire two video's for the price of three.

[correct the example]
(Do not add an apostrophe just because a word ends in 's'.)

Putting an apostrophe before the s in a plural word is a very common mistake and is considered a grammatical howler.

Select the correct version:

Associated lessons:

The apostrophe error with plurals
Apostrophes in time (temporal) expressions
Apostrophes replace letters
Apostrophes to show the plural of abbreviations
Apostrophes show possession