It may take a little practice, but learning the basic hyphen rules will help you become a better writer. Like all aspects of English grammar, hyphen rules are there for a reason, and they also have some exceptions. Learn how to use a hyphen properly to make your writing more professional.
Hyphen Rules and When to Use Them
Six Hyphen Rules With Examples
Understanding the rules is a lot easier when you can see them in action. These are the basic hyphen rules you need to follow, along with examples to show you how.
Rule 1: Use a Hyphen for Two-Word Modifiers Before Nouns
When a modifier consists of two words that join together to describe a noun, you need to use a hyphen. There are a few key things to keep in mind here:
- The two-word modifier needs to come before the noun.
- Both words need to function together to describe the noun.
- Neither word should be an adverb ending in “ly.”
It’s easier to understand this hyphen rule if you see it used. Check out these examples:
- I only eat grass-fed beef.
- The alley was full of hungry-looking cats.
- That is a dog-friendly campground.
Do not use a hyphen if the modifier comes after the noun or if the modifier contains an adverb ending in “ly,” as in these examples:
- The cats in the alley were hungry looking.
- The clearly upset teacher held the students after class.
Rule 2: Hyphenate Compound Words That Are Not Combined
Many compound words are combined or “closed” into a single word, such as “bookcase” and “racecar.” However, there are also many compound adjectives and words that are not combined, and these often use a hyphen to show they are related. Here are some examples of hyphenated compound words:
If you are unsure about whether a compound word is hyphenated, take a moment to look it up in the dictionary.
Rule 3: Use a Hyphen With Many Prefixes
There are three prefixes that nearly always require the use of a hyphen. Always use a hyphen with self-, ex-, and all-, as in these examples:
- The test was self-administered.
- My ex-husband was a computer programmer.
- My children believe I am all-knowing.
Also use a hyphen when the prefix ends with the same letter as the start of the root word:
- We should re-elect the mayor.
- Let’s conduct a meta-analysis of the research.
- It seems to me you’re expressing anti-intellectual sentiment.
In addition, you should always use a hyphen when a prefix comes before a proper noun, as in these examples:
- Some people might consider skipping the parade un-American.
- We will take a vacation in mid-August.
- That is a beautiful pre-Raphaelite painting.
Rule 4: Use a Hyphen With a Few Suffixes
Most suffixes don’t require a hyphen and simply join up as part of the root word. However, there are a few suffixes that need to be hyphenated, including -elect, -style, -based, and -free. You can see them in these examples:
- I love these restaurant-style tortilla chips.
- The mayor-elect will be present at the ceremony.
- It’s a good idea to avoid lead-based paints if at all possible.
- Our backyard is mosquito-free this time of year.
You should also use a hyphen when the suffix starts with the same letter or sound that ends the root word, as in these examples:
- The pitcher has a drip-proof lid.
- Her skirt had a bell-like shape.
- They followed a wheel barrow-wide path.
Rule 5: Hyphenate Compound Numbers and Fractions
Also use a hyphen in some situations involving numbers and fractions. You should always hyphenate compound numbers that you are spelling out, starting at twenty-one and ending at ninety-nine:
- At the age of twenty-one, I set out into the world.
- The car was going fifty-five miles per hour.
- There were ninety-nine bottles of beer on the wall.
Hyphenate all spelled-out fractions as well:
- Two-thirds of freshmen stayed in the dorms.
- This represents an increase of one-fifth of a percent.
- The sled is three and one-half feet in length.
Rule 6: Use a Hyphen to Avoid Confusion
If the word you are writing may be confusing without a hyphen, you should err on the side of adding one. You can see why a hyphen helps keep the meaning clear in these examples:
- The musician re-signed his contract.
- The musician resigned his contract.
- I re-sent the letter.
- I resent the letter.
- The group was made up of small-business owners.
- The group was made up of small business owners.
Practice Using Compound Words and Hyphens
Part of understanding how to use a hyphen involves studying compound words. Take some time to review with fun exercises for compound words so you can properly use a hyphen when the situation calls for one. It may take a little practice, but learning the basic hyphen rules will help you become a better writer. Like all aspects of English grammar, hyphen rules are there for a reason, and they also have some exceptions. Learn how to use a hyphen properly to make your writing more professional.