Dobryy den back at you, S'n'C!
There's a lot of overlap in Slavic languages (not that I'm an expert in these things.) When I was in Yugoslavia I could understand enough words (About every eighth or so) to get by. I was also constantly mistaken for a local (brown hair, brown eyes, high cheekbones, skin colouring - I looked just like one of them.) Folk would get stroppy & think I was playing games with then when, after the initial "Dobryy den", I often appeared a bit dazed & confused by the rest of the conversation. Thought I was trying to be smart!
I have a recently arrived exchange student in one of my classes, from Czechoslovakia ... She nearly fell out of here seat with shock when I hit her with "Dobryy den!" the other morning.
The last thing she expected to come out of her teacher's mouth! But I think I'll have to learn a few more useful things to say ... I'm a bit stumped after that! You probably know more Ukrainian than me!