Thread:User talk:CodeCat/Proto-Slavic/reply (2)

Do you mean the realization of się, se, sa, -ся, etc.? If you look at Slavic translations of to laugh, you'll find that all Slavic verbs are reflexive and have the ending, cognate of sę, the short form. Belarusian merges "-ць" and "-ся" into "-цца". Does this answer your question? In Russian, Proto-Slavic nasal sounds are realised as -а/-я, -у/-ю, e.g. муж, зять, уж, взять, etc.