One of Nuphy's purported ambitions was an Italian phrasebook drawn entirely from opera libretti. It could be called Italian for Opera-Lovers or some such. There was a whole haggling scene from some grand opera (Trovatore?) that he wanted to include for its practical applications. "Quanto?" I'm not sure where he would work in "SUICIDO!" from Tosca, though.

There are a lot of languages with very consistent letter-sound correspondence that I can read aloud with an acceptable accent even though I hardly understand a word I'm saying. Of course, I'm always busted if I hit some numerals!