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The Rules for Using ApostrophesThe apostrophe is only small, but it is a real grammar villain. It is responsible for lots of writing errors. In fact, of all the punctuation marks, the apostrophe is the one with most potential to damage your credibility because your readers will expect you to know how to use apostrophes.
Apostrophes are used in four ways:
- to show possession (e.g., dog's dinner)
- in time expressions (e.g., 2 years' pay)
- in contractions (e.g., isn't)
- to show awkward plurals, but only very awkward plural (e.g., i's and a's)
Table of Contents
- Four Ways to Use Apostrophes
- Three Common Mistakes with Apostrophes
- Use of Apostrophes Explained in Detail
- (1) Using Apostrophes for Possession
- (2) Using Apostrophes in Time Expressions
- (3) Using Apostrophes to Replace Letters in Contractions
- (4) Using Apostrophes in Awkward Plurals
- Using Apostrophes Incorrectly with Plurals
- Video Lesson
- Video on Possessive Apostrophes (A Neat Trick)
- Printable Test
Four Ways to Use ApostrophesWe will cover all four uses of the apostrophe in detail later in the lesson. For now, here are more examples of the four ways to use apostrophes with a key observation for each one:
(1) To show possession.
- a dog's kennel
- our boys' bedroom
- the children's toys
Amazing Tip! The letters before the apostrophe always spell the possessor perfectly. So, in the first example, the letters before the apostrophe spell "dog" (not "dogs"). In the second, they spell "boys" (not "boy"). In the third, they spell "children" (not "childrens"). Look again. The letters before the apostrophe always spell the possessor perfectly. This is a 100% rule. If you remember it, you can ignore the seemingly complicated rules that follow.
(2) To write time expressions.
- a day's pay
- two weeks' holiday
- one month's salary
Amazing Tip! The rule above works for time expressions too! The letters before the apostrophe always spell the unit of time perfectly.
(3) To replace letters in contractions.
Amazing Tip! Some writers confuse contractions with normal words (e.g., it's with its, you're with your). To prevent this error, expand the contraction to the full form (e.g., it is, you are). If your sentence no longer makes sense, then the word you expanded was not a contraction and should not contain an apostrophe. Simple.
(4) To show awkward plurals.
- Accommodation has two a's.
- Hawaii has two i's.
- There are three big if's.
Beware! Using an apostrophe for a plural is disliked by many writers, but it can be efficient. Showing an awkward plural with an apostrophe is condoned by all the leading grammar references.
Three Common Mistakes with ApostrophesApostrophes are responsible for some serious writing errors. Here are the three most common mistakes related to apostrophes:
(1) To show normal plurals.
- three cat's (should be "cats")
- good idea's (should be "ideas")
- two video's (should be "videos")
(2) Randomly before the letter "s."
- He like's pies. (should be "likes")
- Jack agree's with you. (should be "agrees")
- Time fly's like an arrow. Fruit fly's like a banana. (should be "flies")
(3) Using a contraction incorrectly.
- She likes you're dress. (should be "your")
- I can see it's tail. (should be "its")
- They're parents live in Scotland. (should be "their")
Use of Apostrophes Explained in DetailThis section explains when to use apostrophes in more detail and gives examples for each way apostrophes are used.
(1) Using Apostrophes for Possession
- The dog's kennel
- The dogs' kennel
- One dog's dinner
- One dog's dinners
- Two dogs' dinner
- Two dogs' dinners
- children's toys
- women's hat (Here's another issue. It's not always about possession. This means a hat for women. Similarly, "Picasso's painting" is a painting by Picasso. He doesn't own it. Sometimes, it's about "possession" in the loosest terms.)
- people's poet
- men's sizes
- John Wells' report (This is correct. It is used by those who would say "John Wells report" as opposed to "John Wellsiz report.")
- John Wells's report (This is also correct. It is used by those who would say "John Wellsiz report.")
Are You Good at Possessive Apostrophes?Here's a quick test.
(2) Using Apostrophes in Time Expressions
The big question with these is where to put the apostrophe. The ruling is quite simple: the apostrophe goes before the "s" for a single unit of time (e.g., one day's pay) and after the "s" when it's more than one (e.g., two days' pay).
- I never did a day's work in my life. It was all fun. (Inventor Thomas Edison)
- It's not worth it for just two minutes' pleasure.
- I live a stone's throw away.
- a year's insurance (a year "of" insurance)
- two weeks' holiday (two weeks "of" holiday)
(3) Using Apostrophes to Replace Letters in Contractions
- When I was born I was so surprised I didn't talk for a year and a half. (Comedian Gracie Allen)
- Life is something that happens when you can't get to sleep. (Author Fran Lebowitz)
Read more on apostrophes replacing letters
(4) Using Apostrophes in Awkward Plurals
- There are two i's in skiing.
- You use too many but's in your writing.
- There are two Is in skiing.
- You use too many "but"s in your writing.
Using Apostrophes Incorrectly with Plurals
This mistake is most commonly seen when people form the plurals of nouns, but it happens with verbs too; e.g., He eat's pies.
- I like pig's. Dog's look up to us. Cat's look down on us. Pig's treat us as equal's. (These are all wrong.)
- I like pigs. Dogs look up to us. Cats look down on us. Pigs treat us as
- A spoken word is not a sparrow. Once it fly's out, you cannot catch it. (This mistake is sometimes made with verbs too. This should be "flies.")
- Tomato's and oregano make it Italian; wine and tarragon make it French; garlic makes it good. (This mistake is particularly common when forming the plural of a noun which ends in a vowel (e.g., video's , banana's ). It should be "tomatoes" in this example.)
Video on Possessive Apostrophes (A Neat Trick)Here is a short video summarizing how to use possessive apostrophes:
An Infographic Explaining the HistoryThis infographic explains the history behind the possessive apostrophe. It really helps!
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