1. Compound Words:
* Closed: Words that have merged into a single unit (e.g., "rainbow," "notebook," "upstairs").
* Hyphenated: Words that are joined with a hyphen (e.g., "well-being," "long-term," "high-tech").
* Open: Words that remain separate (e.g., "high school," "ice cream," "living room").
General rules for hyphenation:
* Prefixes: Hyphens are often used with prefixes like "pre-", "post-", "anti-", and "non-" (e.g., "pre-existing," "post-mortem," "non-fiction"). But there are exceptions (e.g., "prepaid," "postgraduate").
* Compound Adjectives: Use hyphens when two or more words act as a single adjective before a noun (e.g., "a well-worn path," "a state-of-the-art computer").
* Fractions: Use hyphens for fractions written out as words (e.g., "two-thirds," "one-half").
* Numbers: Use hyphens for numbers from twenty-one to ninety-nine (e.g., "twenty-three," "forty-seven").
* Avoiding ambiguity: Hyphens help clarify meaning (e.g., "re-cover" vs. "recover," "man-eating" vs. "man eating").
2. Suspensive Hyphenation:
* This is used when two words share a common element and the second word omits it.
* Example: "first- and second-year students."
3. End-of-line Hyphenation:
* This is used to break a word at the end of a line when it doesn't fit.
* Dictionaries usually indicate where words can be hyphenated.
Important Note:
* Hyphenation rules can be tricky and have changed over time.
* Refer to a style guide (like the Chicago Manual of Style or AP Stylebook) for the most current and authoritative information.