On grammatical class:

ke'a
pro-sumti: relativized sumti (object of relative clause).
ma
pro-sumti: sumti question (what/who/how/why/etc.); appropriately fill in sumti blank.
zi'o
pro-sumti: fills a sumti place, deleting it from selbri place structure;changes selbri semantics.
zo'e
pro-sumti: an elliptical/unspecified value; has some value which makes bridi true.
zu'i
pro-sumti: the typical sumti value for this place in this relationship; affects truth value.
ca'au
Refers to what is usually assumed to be the argument of tense tags when no explicit argument is given
di'au
pro-sumti and sumyzmico: discourse-interior default it (terbri-specific)
di'ei
pro-sumti and sumyzmico: an elliptical/unspecified value which does not necessarily obey the default setting for the corresponding terbri that is explicitly specified in the definition of the word; has some value which makes bridi true
di'oi
pro-sumti & sumyzmico: discourse-exterior default it
do'ei
impersonal pronoun; generic-you; generic-one; a generalized person
mai'i
pro-sumti: the universal argument/value; syntactically-contextually and type-permitted maximally generic in its typing
nau'o
pro-sumti whose referent's identity is unknown to the speaker
nau'u
what is now; refers to current space/time/situation reference absolutely
tu'oi
null connective operand; used to fill empty places in JOI
tu'oi'u
end connective string, set, list such that the set of terms provided is exhaustive.
zai'o
pro-sumti: the empty argument/value; syntactically-contextually and type-permitted maximally generic in its typing
zu'ai
shows mutual activity between this place and the first place of the current bridi; members participating in the activity are put into the first place (that e.g. can be formed by connecting sumti with {ce} or {jo'u})