Slavic languages have *got* to be the most difficult. Learning the meaning of the words is only a part of it. Being able to say the word even after you've heard it takes a lot of vocal gymnastics.
"Z" is a vowel in Polish, apparently.
Example: "Przemyśl" means industry.
If I ever go to Poland I won't be able to talk about industry because I can't pronounce it.
I don't mind Slavic languages - reading Cyrillic cursive is murder though. HATE it and only bothered to do so well enough to pass that part of the exam. I suppose it's dying like English cursive these days too.
