Compounds cause writers and editors a lot of
problems. English spelling, like English speaking, changes. Many words that
start as open compounds (two or more separate words) morph into hyphenated
compounds (written with a hyphen) and morph further into closed compounds (one
word). The Chicago Manual of Style cites as an example on line, on-line,
online. This is natural in language. That said, here are some points to
remember.
A compound is two or more words acting together as
a single idea: • high school • follow-up • lifestyle Compounds can be nouns, verbs, or adjectives,
seldom adverbs. Whether compounds are open, hyphenated, or closed is mostly a
matter of convention, of agreement. Why should such nouns as credit card be
open, self-confidence be hyphenated, and caregiver be closed? Or
such verbs as to trade in be
open, to double-check be
hyphenated, and to upload be closed? Convention, agreement. When in
doubt, check it out. Compound adjectives can sometimes be tricky because
of their placement in the English sentence. Both regular and compound
adjectives can appear before the noun: • red shoes; the shoes are red • up-to-date report; the report is up-to-date It gets tricky because some compound adjectives are
permanent (found in the dictionary) and some are temporary (created for the
purpose by the writer). Permanent compound adjectives are always written
the same way, whether they appear before or after the noun. Some are always
open: • high school graduate • health care provider • real estate office You’ll notice that these adjectives and many others
like them are formed from compound nouns. When they appear before a noun, and
somehow describe the noun, they function as adjectives. Also, a number of permanent compound adjectives are
hyphenated, whether they appear before or after the nouns they modify: • time-consuming job; the job was time-consuming • one-sided game; the game was one-sided. When it doubt, check it out. Permanent compound
adjectives appear in the dictionary. For temporary compound adjectives—that is,
compounds created by the writer to express a single idea in a specific passage
of writing—the general rule in English is compound adjectives before the noun
are hyphenated, whereas compound adjectives after the noun are open: • city-owned property; the property is city
owned • a well-established firm, the firm is well
established • 30-mile-per-hour speed limit; the speed limit is 30 miles per hour. As you can see, temporary compound adjectives can
be formed using nouns (city, property); adverbs (well);
adjectives (established); and prepositions (per). Another rule: two nouns, whether common or proper,
joined to create a compound adjective appearing before a noun are hyphenated: • student-teacher ratio • Chinese-American relations But NOT, because of convention and agreement African
American woman. When in doubt, check it out. Another rules prohibits combining adverbs that end
in –ly with adjectives to form a temporary compound adjective: • hardly used computer • exceptionally gifted student • amazingly quick response In these constructions the adverb functions as a
modifier of the adjective.
