How To Use Hyphens In Writing

Hyphen Rules and When to Use Them

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.

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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:

free-for-all
state-of-the-art
check-in
mother-in-law
eye-opener
editor-in-chief
six-pack
out-of-date

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.

When to Use a Hyphen vs. a Dash

Understanding the difference between a hyphen and a dash can help you avoid common mistakes. Use a dash to show a break in the text, a range in dates or time, or to create emphasis. Use a hyphen to create a connection between two words.

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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.