Apostrophes

Apostrophes have two uses. They can indicate that a word is a contraction of two other words; and they can indicate a relationship of belonging. The second use is known as the possessive.

The first use may be illustrated by what are essentially contractions of two words into one, such as don’t (for do not); I’m (for I am); and isn’t for is not). Such usages need no further discussion here, because they are generally considered to be inappropriate in formal writing. (It must, however, be conceded, that this consensus is weakening rapidly. Nevertheless, we suggest that you adhere to it, on the simple ground that this will annoy no-one, whereas breaching it will certainly annoy some people.) If you want to test your eye for detail, you might like to try to find the one point in this book – apart from examples of the use and misuse of apostrophes – where we have used such a contraction.

Turning to the possessive use of apostrophes, the basic rules are:

adding ‘s to a singular noun creates the possessive form (so the girl’s bicycle means the bicycle belonging to the girl); and

where a plural ends in s (as most English plurals do), adding the apostrophe on its own creates the possessive form, without the need for a further s (so the girls’ bicycles means the bicycles belonging to the girls).

Where a singular noun ends in s (which is most likely to be the case where names (such as Jones) are concerned, either ‘s or an apostrophe on its own is acceptable: Tom Jones’ bicycle or Tom Jones’s bicycle). However, where a word ends with ss, the possessive form does require ‘s, as in the boss’s bicycle.

The only possessive forms which do not use apostrophes are possessive pronouns, such as his, hers, theirs and its.

Unfortunately, one aspect of the use and non-use of apostrophes in the context of possessives causes persistent and serious difficulty for many people. These people are tempted to apply the basic rule of adding ‘s to it when they wish to create the possessive form. However, this overlooks the point that, as we have just seen, with possessive pronouns the possessive form is built into the word itself (so that no apostrophe is needed). Using an apostrophe in an attempt to mean of it is doubly unfortunate because it’s is a perfectly legitimate word in the context of informal English, where it is an example of the other type of use of apostrophes (namely contractions) and where it means it is. So, if you write the dog was playing with it’s bone, what you are really saying is the dog was playing with it is bone. This cannot be what you really meant.

Fortunately, the correct use of it’s presents no difficulty provided you follow the advice to avoid all such informal expressions in academic work. If you do try to follow this advice, but carelessness nevertheless leads you to write it’s in a first draft, you will know that it must be corrected (either by removing the apostrophe or by writing it is, depending on what you meant).