1. Compound Words:
* Joined words: Hyphens join two or more words to create a single, compound word.
* Examples:
* well-being
* high-tech
* self-esteem
* mother-in-law
* twenty-one
2. Prefixes:
* Before a proper noun: Hyphens are used before a proper noun when forming a compound word with a prefix.
* Examples:
* anti-American
* pre-Columbian
* un-English
* post-World War II
* Before a capitalized word: Hyphens are used before a capitalized word when forming a compound word with a prefix.
* Examples:
* non-European
* pro-Republican
3. Fractions and Numbers:
* Fractions: Hyphens are used when writing out fractions as words.
* Examples:
* two-thirds
* one-half
* three-quarters
* Numbers: Hyphens are used in compound numbers from twenty-one to ninety-nine.
* Examples:
* twenty-four
* sixty-seven
* eighty-nine
4. Avoiding Ambiguity:
* Prefixes ending in "a" or "o": Hyphens prevent ambiguity with words that could be interpreted as a different word.
* Examples:
* re-sign (meaning to sign again)
* re-form (meaning to form again)
* co-op (meaning cooperative)
* "ly" adverbs: Hyphens are used when an "ly" adverb precedes a participle.
* Examples:
* poorly-written
* newly-elected
* deeply-rooted
5. Other Uses:
* Suspended hyphens: Hyphens are used to connect two words, but the second word is only used once at the end of the phrase.
* Examples:
* ten-, twenty-, and thirty-year plans
* Spelled-out compound numbers: Hyphens are used in compound numbers, even when written out.
* Examples:
* forty-two
* one-hundred-and-one
Important Notes:
* Consistency: Always follow the rules consistently.
* Dictionaries: Consult dictionaries for specific compound words to see if they are hyphenated, closed, or open.
* Style guides: Some style guides have different preferences for hyphenation, so follow the guide you're using.
Remember: Hyphens are essential for clarity and consistency in written English. Using them correctly can significantly improve your writing.