There’s nothing as easy as using a hyphen… except using hyphens correctly isn’t easy at all. Hyphens are considered a “look it up” punctuation because there are many additions and exceptions to these rules, but if you understand the basics of hyphen usage, you’ll be looking up the rules a lot less often. So, here are the top seven of many guidelines that govern hyphen usage.
1) Use hyphens when writing ages, periods of time, fractions, or spelling out any number between 21 and 99.
e.g. there are fifty-two sheep; we have an 8-year-old; one-fifth of all statistics are made up
2) Do not use a hyphen after adverbs ending in -ly
e.g. the elegantly dressed man
3) Use hyphens to connect words that have a combined meaning
e.g. the happy mother-in-law
4) Use hyphens to create most compound adjectives; this could be a noun + adjective, noun + participle, or adjective + participle.
e.g. a woman-owned business, the green-hued wall
5) If your compound adjective occurs before the noun it modifies, use the hyphens. If it occurs after, get rid of them.
e.g. it was a run-of-the-mill project; her project was run of the mill
6) Use a hyphen when two nouns are used as a verb
e.g. I want to ice-skate
7) Use a hyphen after prefixes when the prefix ends in the same letter (usually a vowel) as the modified word begins
e.g. we re-examined the document
Don’t confuse a hyphen with the longer dash. Hyphens join together words while dashes separate clauses and thoughts. Hyphens are a punctuation mark with a lot of rules and a lot of exceptions. Because very few people will know exactly when to use a hyphen or not, it’s safe in questionable situations or for clarity to add any hyphens you want. Just be consistent and stick with whatever style you choose. You’ll be a hyphen-master in no time.