Language Studies for Travel & My Writing Research

I am sporadically studying German and French, hard at work so that I can better decipher centuries-old letters by Sophia of Hanover that haven't yet been published in English. Fluent in neither, I flit from one to the other like Duo the Owl... but now there's Italian, too! One of my novels is set partially in Venice and Rome, and since I'm planning to go see these historic cities for myself, I've just switched to Italian this past month. So... my progress is will-o'-the-wisp from language to language, and I'd actually even reverted to Spanish for a while, too, since I had the Yucatan, Mexico trip last month. That was after our Montreal Spring trip, for which I'd brushed up on French. I was astonished at how essential and useful my broken, rudimental Spanish (mostly learned in high school) was while in Mexico, so much so that I woke up one morning, panicking that I was planning to go to Italy without knowing the first word of Italian. At this rate, it's pretty certain I'll never be fluent in any of these languages, but it certainly helps to be able to read signs and menus, say hellos and goodbyes and whatnot... Italian is very similar to French and Spanish, so while it's perhaps a little confusing, it's far easier to figure out sentence meanings this go-round! Sophia of Hanover and her siblings wrote in a polyglot way, sometimes in one language, sometimes another, sprinkling in words from other languages. She spoke German, Dutch, Italian, English, and French fluently, from what I understand. I haven't touched Dutch yet, but we will see what the future holds! I find the Duolingo app helps me to be consistent, but old-fashioned me does find it helpful to supplement at times with actual language books...