As a copy editor, I have to read a lot of freelancers’ articles, and often times, I am amazed at the interesting grammar choices they bring into the sterile, grammar disease-free environment of our editorial office. They bring in grammar flavors of the month, going in cycles of wanting to put a comma here one month and then the next deciding there really wasn’t supposed to be a comma there after all. What is hilarious is they all seem to pick up the same flavors at the same time. And when they all pick them up at the same time, sometimes it tricks the copy editor into thinking they have missed something, and that is when the copy editor needs to slap themselves and say: “No! These freelancers are wrong!”
The most recent flavor, or STD as I like to joke, is hyphenating -ly adjectives with other adjectives, eg., a partially-deaf individual or the publicly-owned complex. Where they picked this up, I have no clue, but it is wrong. -ly adjectives are never hyphenated with another word per the AP Stylebook and Chicago Manual of Style.
So what can you hyphenate? Well, you can hyphenate two words that do not end in -ly for one, eg., blueish-green sea, worst-case scenario, well-read child, and so on. You also hyphenated ages when they are in front of the noun like the five-year-old child or the 100-year-old house. The linked to chart is a lifesaver when it comes to tackling the hyphen. Another friend is the dictionary, which will show compounds that are hyphenated.
In high school, I had a teacher who whenever we had questions would always tell us to look it up. At the time, it would drive me crazy, but nowadays I am exceedingly grateful, because it has made me capable of hunting down my own answers — to be self-reliant. It is a skill all writers need to have, and that is why you need the tools to find the answers to any questions you might come across while writing. Purchase a stylebook (most publishers use the Chicago Manual of Style) and use it! Have a dictionary on hand to look up not only meanings, but also hyphenation and compounds without hyphenation. No one is going to hold your hand while you write, and if you intend to publish, you need to weed out as many mistakes as possible, which means look it up!