I see many words that should be hyphenated spelled as one word, the most common is e-mail. Here’s a rule to remember without exception: When the word is formed with a single as the first syllable, hyphenate or open. Q-tip, V neck, U-turn, e-publishing, X-ray, A-line, G-string, D day.
I also see hyphens that aren’t needed. Commonly mishyphenated words include: ongoing, under way, a priori (or any Latin phrase), bona fide, vice versa, and ad hoc.
Avoid using a hyphen with an -ly adverb: widely known, thinly coated, readily available.
Rules are fine, but most of the time you can use common sense. For instance, if the reader will stumble over a word because of a missing hyphen, it’s wise to add one: Do-able, co-worker, pre-wedding, city-wide. Another situation arises when the compound word repeats letters, creating an awkward spelling: anti-inflammatory, re-emphasize, multi-item, shell-like. You don’t want to jar your reader from your story with funny looking words like antiinflammatory, reemphasize, multiitem, shelllike, right?
It’s a good idea to hyphenate when the root word is capitalized or a numeral: pre-Columbian, Buddha-like, un-American, pre-1900s, post-1950s. Likewise, hyphenate numbers that are spelled out or are stated as fractions: twenty-one, sixty-seven, one-fourth, but not two-word numbers combined with a fraction: forty four one-hundredths of a percent.
Commonly accepted hyphenated words are those with the prefix ex, self, or all, or words with the suffixes free, odd, elect. Examples: salt-free, ex-husband, self-employed, all-encompassing, ninety-odd dollars, president-elect.
Don’t expect to remember all this. Keep a good grammar reference handy, such as Grammatically Correct: The Writer’s Essential Guide to Punctuation, Spelling, Style, Usage and Grammar by Anne Stilman.
Great post Cheryl, but did you know that it’s possible to check a lot of the issues with hyphens automatically using an add-in that we developed? PerfectIt spots any words hyphenated inconsistently in your text and has custom settings for each compound prefix, as well as fractions and numbers. It’s free to try and all of the details can be found at http://www.intelligentediting.com.