|Definition - A two-or-more word adjectival or adverbial phrase.|
1. Hyphenate them to reduce ambiguity
2. Don't use hyphens after adverbs that end in ly.
quickly-forgotten relationship (bad)
quickly forgotten relationship (good)
3. Don't hyphenate the modifiers if they follow the noun that is being described.
his blood is Type A
4. Don't use a hyphen after the word very .
very-quickly forgotten relationship (bad)
very quickly forgotten relationship (good)