If you ease the burden of something, you might say that you “lightened” it. If you make something less messy, you’ve “tidied.” But not “tidy-ened.” When you make something easier to understand, you’ve “clarified” — but not “clearened” or “claried.” And for that matter, if you go around your room straightening and correcting things, you’ve “spruced” it up. Not “sprucened” — but guess what — you actually have “sprucified.”
“Sprucify” comes, obviously, from “sprucing up.” It comes from “spruce”, which back in the 1500s meant “lively” or “brisk,” and by 1600 came to mean “neat” or “attractive.” That was probably thanks in part to Shakespeare, who used it in “Love’s Labor’s Lost.” That sense of “spruce” is still around, but it’s almost always used in the form “sprucing.” You can still find something like “Strahan looked spruce in a sharp new suit and white shirt open at the collar,” which is from 2006, but at this point it’s pretty rare.
“Sprucify” was popular in the 1600s and 1700s. It was formed by adding the “-ify” suffix, which is a technique borrowed from Latin. It’s pretty common, and you’ll see it in words like “personify” and “acidify.”
In English, of course, there’s always more than one way to modify words, and “straight” turns into “straighten” instead of “straightify” based on the Old English approach instead of the one in Latin. In general (sort of), if you find a word that uses “-en”, the root word is likely to come from Germanic languages like Old English. Also sort of, when a word is modified using “-ify,” chances are that the root is from Latin or a Latin-based language like French or Italian.
On the other hand, these rules aren’t going to be useful forever. Just think; at some point somebody researching the etymology of a language like the one invented in the second Martian colony might say something like “this word is modified in a particular way because it’s derived from the English language, where the rule was…no, wait, the rule in English was…I mean… oh forget the whole idea; I’m moving to Saturn where things are more clarificated.”
