GRAMMATICALLY
CORRECT
Very occasionally, it may not be clear whether the word that follows an adverb is linked with the adverb or with whatever lies on its other side. For example: Try as she would, she couldn't getaround the maddeningly slow moving van.
Is the reference here to a moving van that is maddeningly slow or to a plain old van that's moving maddeningly slowly? If the former is intended, a hyphen to combine maddeningly with slow would make it clear which word gets linked with which. Try as she would, she couldn't getaround the maddeningly-slow moving van.
IN MOST CASES, DO USE A HYPHEN FOR ADVERBS THAT DO NOT END IN LY The rules are more complex for adverbs that do not have ly endings, probably because such words may not be as instantly recognizable as adverbs. Style guides do not completely agree on how to handle these situations. Rather than prescribing the way to do it, this section will simply describe the alternatives. Authorities agree that in most cases, when a "non-/?/" adverb combines with another word to form a compound adjective modifying a noun, do link the two with a hyphen. He handed in a well-written essay. She stared into the still-glowing embers. His much-loved pet gerbil was getting old. It was clearly an ill-advised plan. A fast-talking salesman cornered them and wouldn't leave. The cat let out a high-pitched yowl when he accidentally dropped the cantaloupe on her head.
As before, if the compound follows the noun, omit the hyphen, unless the compound takes one as part of its proper spelling. Note that the hyphen is part of the spelling in quite a few of these cases. The essay was well written. The embers were still glowing. The gerbil was much loved.
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