All Slavic languages: one, two, three.. vs "once, two, three...

  • Polish for example.
    • jeden, dwa, trzy
    • raz, dwa, trzy
    The latter is quite popular in various situations, because "raz" has only one syllable - just like dwa and trzy.
    In Bulgarian both are possible
    1. raz, dva, tri
    2. edno, dve, tri

    When counting in Bulgarian, we always use the neuter forms for one and two. With raz we use the masculine dva (I guess because raz is masculine).