While the humble apostrophe is not the least understood piece of punctuation in the English language, that honor rests with the semicolon, it is by far the most frequently misused. Despite this, the apostrophe is not evil, but simply misunderstood. If you care to understand its minor mysteries, here is a simple guide.
The apostrophe performs two functions, which is very industrious of it, but can also be a source of confusion. It is used to denote possession (ownership), and contractions (the removal of letters).
Possession
In this case, simply place the apostrophe at the end of the name of whatever has possession of the object. The forms for singular and plural sometimes cause confusion here, but it's actually pretty simple.
Singular: It was the Gnome's cow.
In this case the cow belongs to one Gnome, so simply add an apostrophe and an s.
Plural: It was the Gnomes' cow.
In this case the cow belongs to multiple Gnomes, so the apostrophe goes after the 's' denoting a plural. This form denotes collective ownership, so is not present in American English (jk
).
And that's all there is to it for possession.
Contractions
In this form of usage the apostrophe is placed wherever letters have been removed; this may be from a single word or a compound word. The rule here is that the apostrophe simply takes the place of the missing letter(s).
Examples
Has not: Hasn't
Cannot: Can't
It is: It's
Replace letters with apostrophe... simple!
Its/It's (a special case)
It's is either 'it is' or 'it has'. Its always denotes possession, and never a plural (and no apostrophe is used).
Examples
Contraction: It is big: It's big
Possession: The Pit Fiend was carrying its skateboard.
Most common misuse
The most common mistake is the use of the apostrophe where there is a plural, but no contraction or possession. People do this alllllll the time.
Example
The DM's are a bunch of grammar Nazis.
In this case the DMs do not own anything else in the sentence, and there are no missing letters. No need for an apostrophe! The sentence should read as follows.
The DMs are a bunch of grammar Nazis.
Anyway, I'm not entirely sure why I'm writing this (probably not very helpful) guide, so I'm going to stop now!
The apostrophe performs two functions, which is very industrious of it, but can also be a source of confusion. It is used to denote possession (ownership), and contractions (the removal of letters).
Possession
In this case, simply place the apostrophe at the end of the name of whatever has possession of the object. The forms for singular and plural sometimes cause confusion here, but it's actually pretty simple.
Singular: It was the Gnome's cow.
In this case the cow belongs to one Gnome, so simply add an apostrophe and an s.
Plural: It was the Gnomes' cow.
In this case the cow belongs to multiple Gnomes, so the apostrophe goes after the 's' denoting a plural. This form denotes collective ownership, so is not present in American English (jk

And that's all there is to it for possession.
Contractions
In this form of usage the apostrophe is placed wherever letters have been removed; this may be from a single word or a compound word. The rule here is that the apostrophe simply takes the place of the missing letter(s).
Examples
Has not: Hasn't
Cannot: Can't
It is: It's
Replace letters with apostrophe... simple!
Its/It's (a special case)
It's is either 'it is' or 'it has'. Its always denotes possession, and never a plural (and no apostrophe is used).
Examples
Contraction: It is big: It's big
Possession: The Pit Fiend was carrying its skateboard.
Most common misuse
The most common mistake is the use of the apostrophe where there is a plural, but no contraction or possession. People do this alllllll the time.
Example
The DM's are a bunch of grammar Nazis.
In this case the DMs do not own anything else in the sentence, and there are no missing letters. No need for an apostrophe! The sentence should read as follows.
The DMs are a bunch of grammar Nazis.
Anyway, I'm not entirely sure why I'm writing this (probably not very helpful) guide, so I'm going to stop now!
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