Hyphenating temporary compounds
Hyphenate temporary compounds according to current dictationary usage and using the following
Hyphenate a compound that contains a noun or an adverb (except adverbs ending in -ly; see Hyphenating adverbs ending in -ly) and a participle that together serve as an adjective modifying the noun they precede. Do not use the hyphen if the compound follows the noun.
decision-making methods (alt: methods of decision making)
most-read reference in the library (alt: That reference is the most read in the library)
The patient participated in a placebo-controlled trial (alt: The trial the patient participated in was placebo controlled)
Hyphenate a compound adjective phrase when it precedes the noun it modifies but not when it follows the noun.
side-by-side comparison (alt: compared side by side)
Hyphenate an adjective-noun compound when it precedes and modifies another noun but not when it follows the noun.
low-quality radiographs (alt: radiographs of low quality)
high-altitude sickness (alt: sickness at high altitude)
very low-birth-weight infants (alt: infants of very low birth weight)
NOTE: In most instances, middle, high and low adjectival compounds are hyphenated.
Hyphenate 2 or more adjectives used between coordinating or conflicting terms whether they precede the noun or follow.
The false-positive test results were noted.
The test results reported were false-positive.
Black-and-white illustrations were provided to the court.
The illustrations provided to the court were black-and-white.
Hyphenate color terms in which 2 elements are of equal weight.
blue-gray eyes
yellow-green contusions
However: Yellowish green contusions.
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