Many words start with prefixes; e.g., nonresident, antitrust, coparty, and a spate of others. As a writer, you must learn the rules of hyphenation. So let's start with this observation:
Nearly all words formed with prefixes are not hyphenated.
Yet many writers will spell some prefix words one way and virtually identical words another way: non-resident and nonobvious or pretrial and pre-verdict.
In law, older versions of the Federal Rules of Civil Procedure were hopelessly confused. The heading to old rule 21, for example, contained two prefix words, each treated differently:
"Misjoinder and Non-Joinder of Parties." Rule 13(g) spoke of "co-party." Yet the Federal Rules correctly left out the hyphens in "Interpleader" and "Multidistrict Litigation."
The spell-checkers of MS Word and WordPerfect don't have a clue about correct hyphenation, so they will "reject" many correctly spelled words.
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