Mnogaïa Lietea (Mnogaya Lietea), traditional Russian song harmonized for mixed-voice choir, in a rendition and transliteration by members of the Ensemble Choral de Vincennes directed by Michel Martzolf:
This page, very simple, is a bit like Multi ani (ref. ACJ 390), a festive song for all occasions, as well at the end of a religious service as during a meeting between friends or between choirs...
It should not pose any problem as much by the language (it counts only 2 words!) as by the music (several voices often parallel and/or answering each other).
For 4-part mixed choir (SATB):