Business Writing Essentials
Describers that describe describers
When an adjective describes another adjective, you often need to use the hyphen to make things clear:
He has a difficult, stressful job.
[both describe the noun]
He has a high stress job.
[what describes what?]
He has a high-stress job.
When an adverb that ends in -ly describes a verb that is used to describe a noun, it should not be linked with a hyphen:
Our recently elected leader quoted a widely accepted theory.
In multi-word phrases that describe another word, use the hyphen, but not when the phrase stands alone:
They promised on-time delivery, but our delivery was not on time.
To create a compound noun that lacks a noun as one of its elements, use the hyphen:
We got the go-ahead to sell the two-by-fours, but it became a free-for-all.
To join the prefix co to a word that starts with the letter o, use the hyphen (exceptions: cooperate, coordinate):
The co-organizer of the event asked us to cooperate.
To join a compound noun that ends with a prepositional phrase, use the hyphen:
The attorney-at-law explained who had the right-of-way.
To join a compound noun that shows one person or thing has two functions, use the hyphen:
I asked the realtor-owner to turn on her fax-printer.
With the first of two hyphenated adjectives linked to a common word, use the hyphen:
I prefer a two or three-page proposal.
[two describes what?]
I prefer a two- or three-page proposal.
When spelling out any number between 21 and 99, use the hyphen:
Twenty-five of the 36 emails were received and opened.
When using a period of time to tell the age of someone or something, use the hyphen:
That two-year-old project really is two years old.
When spelling out a fraction that is not introduced with a or an, use the hyphen:
More than one-third of us spent a fourth of our time on it.
When the meaning of a sentence becomes confusing without the hyphen, use the hyphen:
Our headquarters location has little town charm.
Our headquarters location has little-town charm.
Hyphens join things by sticking close to them, so avoid putting spaces next to the hyphen:
There must have been 100 - 150 people at the game.
There must have been 100-150 people at the game.
When you want to separate things—or draw attention to them—use the n-dash or the m-dash, not the hyphen.
There are so many rules and exceptions for this stuff that you will need to rely on a trustable reference for real-world writing, such as The Gregg Reference Manual.
Course: Business Writing Essentials