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Hyphens, En Dashes, Em Dashes
Q. I understand that adjectives modified by adverbs ending in -ly are always open. But what about instances such as “provide developmentally appropriate information”? My instinct is not to hyphenate, but I don’t think developmentally is an adverb here, so I’m not sure if the always-open rule applies.
A. Developmentally is indeed an adverb modifying the adjective appropriate. It’s exactly the kind of situation we’re referring to in CMOS 5.93. Chicago style is not to hyphenate.