Apostrophes are an endless source of confusion for writers. So I thought you might enjoy watching this short video on the subject:
VideoJug: How To Use An Apostrophe
Below is a transcript of the video. Learn it all, my friends!
Step 1: Missing letters
Apostrophes are primarily used to indicate missing letters. Whenever you are taking away letters to shorten a word, or merge two words, put an apostrophe in their place. This is how we distinguish between words like he'll and hell, she'll and shell.
And it works with years too:
The summer of ‘69
It's important to remember the meaning of what you are writing. A common mistake is to write:
You could of won already. When we really mean: You could have won already. Which can be written as: You could've won already.
Step 2: Ownership
An apostrophe also shows who owns what in a sentence. For instance:
The boy's dinner. (The dinner belonging to the boy)
And it's the same if the word ends with an s:
The bus's arrival.
Apostrophes are also used for something that is owned by more than one person. When the boy's dinner is written as the boys' dinner, it means the dinner is shared between 2 or more boys.
This could cause massive confusion if not done correctly:
Large children's playground (a large playground for children)
Large childrens' playground (a playground for large children)
It works the same with time:
One week's time (in the time of one week)
Two weeks' time (in the time of two weeks)
One pound's worth (worth one pound)
Two pounds' worth (worth two pounds)
Step 3: Exceptions to the rule
There are a few exceptions to the rules, where the ownership apostrophe and missing letters apostrophe seem to clash. While they are exceptions, getting these wrong is the best way to annoy a punctuation-stickler. Watch out for words like:
It's (it is) As in: It's a lovely day today! Or: It's got to be done today (it has)
Its (belonging to it) As in: Dont pull its tail.
Who's (who is) Who's doing the counting? or Who's been to Newquay?
Whose (who it belongs to) Whose shop is this?
You're (you are) You're never going to believe this
Your (belonging to you) Where's your coat?
Step 4: Improper English
Finally, we also use apostrophes to show that someone isn't speaking ‘proper' English:
The Grumpy Examiner says, "Get apostrophes right, or else!"
Play an apostrophe game by clicking here, and there is an excellent quiz here.