srepxrvati fu'ivla

x1 is Serbo-Croatian (Serbian/Croatian/Bosnian/Montenegrin) in aspect x2

See also slovo, nanslovo, bolgaro, slovino.

In notes:

nanslovo
x1 is South Slavic/Yugoslavian in aspect x2.
srepxrvatybau
x1 is the Serbo-Croatian language used by x2 to communicate x3.