Okay, as I have confessed, I have a bad case of hyphenitis. I like hyphens. They make me very happy.
But there are places you don’t use hyphens. For example, when you have a modifier that consists of an adverb-adjective, you don’t need one. Basic rule: If you have a word ending in -ly, don’t use a hyphen. For example, don’t hyphenate “A highly effective sentence.” The “highly” doesn’t modify “sentence,” it modifies “effective.” It’s not ambiguous.
Being a nut for hyphens, I would love to hyphenate it anyway. But I’m not allowed to.
Then there are those words that have to be hyphenated, like “high school student.” Anymore, you definitely have to hyphenate that one. There are a lot of students who go to school high.
Then there are those pesky words that are sometimes hyphenated, sometimes not: well, ill, better, best, little, lesser, and least. What’s the rule? Hyphenate before a noun but not after: “A well-dressed man,” but “The man was well dressed.” But even before the noun, don’t hypenate if modified: “A very well dressed man.” Don’t ask me why — the mysteries of life are deep.