Actually the Bulgarian language should not pose too many problems to those who already master Russian. In a way, it looks like a simplified version of Russian, and it is probably the only Slavic language that does not have the noun declination, which is arguably one of the most difficult features of languages like Russian, Polish and Serbian. There are however some catches and you may really want to avoid a couple of them, because it could get embarassing. Like, really embarassing:
булка – when a Russian wants a булка, he goes to the backery (Rus. white bread). In Bulgarian, a булка is a young woman, a девушка.
година – the word is actually preserved in poetic Russian and in Ukrainian and Polish, where it means “hour”. In Bulgarian, however, people wish each other “честина нова година” on New Year’s Eve.
гора – it is true that some горы (Rus. mountains) are covered with гори (Bg. forests), especially in Bulgaria.
друг – a Russian “friend” is a just “another” guy in Bulgarian.
дума – in the Russian дума (Parliament, but also thought) people generally engage in long debates using a lot of думи (Bg. words)
майка – a Russian майка (undershirt, singlet) is not exactly the most stylish piece of clothing that your майка (Bg. mom) can wear
направо – (на) право – don’t be angry if you get lost in Bulgaria because somebody told you to go на право (Bg. straigh on) and you turned направо (Rus. right) instead
палец – not all пальцы (Rus. fingers) are a палец (Bg. thumb)
стол – if people invite you to take a стол (Bg. сhair) to have a seat, don’t be surpirsed if your guests roll their eyes when you sit on the стол (Rus. table)
чурка – I guess some guys would like to brag that their чурка (Bg. penis) is large like a чурка (Rus. chock, block of wood) – sorry for the comparizon, but you get the picture, right?
шутка – in Russian a шутка is a funny joke, but this is probably the one mistake that you really might want to avoid, and please don’t complain that we did not warn you: in Bulgarian this would be a not extremely polite reference to the female sexual organ … could it get any worse than this?
If you know some other Bulgarian-Russian false friends and you are a good person and want to help our readers, please do contact us here.