Unit modifiers hyphenation

Do not hyphenate unit modifiers if the first word is an adverb ending in ly . 

Hyphenate unit modifiers containing the adverbs well , still , ever , ill , and little . 

Hyphenate unit modifiers containing a comparative or superlative if the meaning could be different without the hyphen. 

Do not hyphenate unit modifiers that are chemical names. 

Hyphenate unit modifiers that contain spelled-out numbers. 

Hyphenate unit modifiers of three or more words. 

Hyphenate unit modifiers containing three words when similar two-word modifiers are hyphenated. 

Hyphenate unit modifiers used as predicate adjectives. (Predicate adjectives are usually used with the verb to be they are adjectives that modify the subject but come after the verb.) Usually, only unit modifiers that consist of nouns and adjectives or nouns and participles can be used as predicate adjectives. 

Hyphenate unit modifiers containing a number, a unit of measure, and a word. 

Do not hyphenate unit modifiers containing three or more words, even if similar two-word modifiers are hyphenated, when doing so would break other rules. For example, do not hyphenate unit modifiers if one of the words is a proper name. Do not hyphenate unit modifiers that are two-word chemical names. 

Hyphenate unit modifiers made up of a single letter or number and a noun or adjective. 

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