The apostrophe seems like a straightforward form of punctuation, but there are a few tricky situations you’ll have to navigate.
For example, when writing informally, you may have occasion to use a double possessive.
Example: That idea of Rob’s is brilliant.
Unlike a double negative, a double possessive is grammatically fine (though I wouldn’t recommend using it in academic writing or any other communication requiring a high degree of formality).
Did you know about the double possessive? If no, read on and find out more. If yes, everyone can use grammar refreshers, so still read on to see if you’ve forgotten anything.
It’s common knowledge that the apostrophe is used to indicate ownership. What can trip you up is what to do when a name (also called a proper noun) ends in s. Let’s look at the recommendations of the two most popular stylebooks. The Associated Press Stylebook says to use only an apostrophe in such an instance.
Example: Achilles’ heel.
The Chicago Manual of Style, on the other hand, recommends using both the apostrophe and the s.
Example: Charles’s report.
Please note that the Chicago manual stipulates exceptions for the names Jesus and Moses, which simply use an apostrophe (it cites tradition as the reason):
Examples: Jesus’ teachings and Moses’ law
Both style books also cite an interesting exception to the general rule about using an apostrophe and s for nouns that do not end in s. If the word actually ends with an s sound and is followed by a word that actually begins with an s, then you only need to add an apostrophe.
Examples: For conscience’ sake or for appearance’ sake
When the object of a sentence is in a plural form and you also have more than one subject, you can indicate individual ownership by adding an apostrophe and s (if applicable) to each name.
Example: John’s and Lisa’s offices. (In other words, John has an office and Lisa has another office.)
If I wanted to indicate joint ownership, I would only add the apostrophe and an s to the last name.
Example: John and Lisa’s office (they share one office).
This possessive form is advocated by both the AP and Chicago style books. However, some grammarians feel that“John’s and Lisa’s office” is an acceptable way to indicate joint ownership, so if you aren’t following either of those style books, you have the option of using that form.
Another tricky situation for most is the possessive form of the word it. You don’t use the apostrophe in this instance. The trick I use in order to remember whether or not to include the apostrophe is the idea that it is a pretty laid-back word when it comes to possessions.
The apostrophe is often used to eliminate confusion when forming plurals, particularly the plurals of letters and digits.
For the Chicago manual, individual letters should be italicized, in which case an apostrophe isn’t needed when pluralizing the word.
Example: He uses way too many xs and os at the end of his letters.
However, the manual also states when a letter is part of a popular saying, it is not italicized and in that case, an apostrophe is used with an s to make plural forms.
Example: Dot your i’s and cross your t’s.
Both the AP and the Chicago manuals state that when the letters are a designation of academic achievement, they are capitalized and use the apostrophe in their plural forms.
Example: Her report card was all A’s.
Interestingly, the Chicago manual recommends using the apostrophe and an s to form plurals within quotation marks.
Example: Her only response to their barrage of questions was a series of“possibly’s.”
Many style guides differ about whether to use the apostrophe with plurals of numerals, but both the AP and Chicago manuals advocate no apostrophe.
Example: The 1900s
So how did you do? Did you learn anything new? I definitely learned a few things while preparing this post. In fact, if you have any questions about the apostrophe, drop me a line in the comments section and I’ll help you out.