Rules and Examples
There are many rules associated with using hyphens. We're going to explore the rules that you'll use most often in your writing.
Rule #1
Use a hyphen to create a compound adjective when that adjective is used before a noun in a sentence.
This rule is easier than it appears. We often use adjectives, descriptive words that modify nouns, to add details to our sentences. Sometimes, we want to use two adjectives together to create a single modifier. These two adjectives, when joined by a hyphen, become a compound adjective.
Examples:
- Alexa's parents ordered an extra-special cake for her birthday party.
- My new apartment has on-street parking.
Rule #2
When a prefix is used with a root word and that root word bends with the same vowel as the prefix, use a hyphen to avoid confusion.
Example:
The voters re-elected the president for another term.
Rule #3
When the prefixes 'ex-', 'self-', or 'all-' are used to start a word, use a hyphen between the prefix and the root word.
Examples:
- Her ex-husband is getting remarried.
- Mario was known as a self-assured athlete.
- Stella's new job proved to be all-encompassing.
Rule #4
Use a hyphen between two numbers in a compound number. A compound number is a number that includes two number words within it.
Examples:
- We are going on a cruise for my cousin's twenty-third birthday.
- The one-year-old smashed his birthday cake in his face.
Rule #5
A hyphen should be used between two parts of a compound word any time that combining those two parts could create confusion about the word's meaning. Sometimes, when prefixes or suffixes are added to words or two words are combined, the resulting word may have a different meaning than the writer intends.
Example:
The bank asked the Smiths to re-sign their loan application.
In this sentence, the word 're-sign' means 'to sign again.' However, without a hyphen, the word would read 'resign', which means 'to leave a position.'