A striking example is the Rosetta stone – a parallel Egyptian-Greek text, according to which the ancient Egyptian hieroglyphs were deciphered.
Another example is the parallel English-Russian Bible, by which you can quickly improve your knowledge of the language.
My dream is to find a book with parallel texts of all the hits I know, so that there is less chaos in my head when I hum them (real hits!). If the hit has a lot of slang, it would be nice to have a sensible comment.
In English, slang is a powerful source of development. All words may have once been slang. But our “scientists” (and post-Soviet ones) pretend that they do not understand this, hindering the development of the language. But official “scientists” were disconnected from the Russian language in Ukraine.
Therefore, paradoxically, the Russian language in Ukraine received a powerful impetus for development.
For example, no one hinders in the Ukrainian version of the Russian language to change the letter “и” to “i”, which takes up much less space and is better perceived. And thereby correct the mistake of Lunacharsky, who in a hurry threw out letters from the alphabet. By the way, our classic of the Ukrainian version of the Russian language Andrei Kurkov, ones upon a time, approved such a replacement.