Intermission: "Synthetic" language
Japanese is synthetic. The linguistics term "synthetic" means that a language likes to synthesize (!) words out of small parts. Generally speaking. Above all, "synthetic" does not mean a manufactured, synthesized language itself.
Japanese is a synthetic language, due to it piling verb conjugations on top of eachother like 見られたくなかった. Piling things together like this is called "agglutinative". When you make complicated meanings with single pieces that have several implications, that's called "fusional". Japanese is not fusional.
The opposites of synthetic are "analytic" and "isolating". Chinese is both analytic and isolating. English is considered an analytic language because it loves function words and has relatively few productive inflections, but less isolating because it loves derivational affixes.
The exact definitions of "analytic" and "isolating" tend to be fuzzy, because extremely analytic or extremely isolating languages tend to be both, not just one or the other. Modern linguists think that categories like these, in the vague sense, aren't that useful at categorizing all the languages, just the ones that grammar people liked looking at.