What do you do for Estne when it is PLural?
do you do the same thing or not?
Do you mean when asking a question? The -ne suffix is general.
Sumne? = am I?
Esne? = are you?
Estne? = is he/she/it?
Estisne? = are you all?
Suntne? = are they?
Of course, this is only for use when a question word (ubi, quando, quid, quis, quomodo, etc.) isn't present (the -ne ending turns a statement into a yes/no question). :)
Volgav vitsenanieff nivya kevach varatsach.