Verbal Valency and Tense Inflections in Finnstek

(part.)=untranslated particle
(fut.)=future tense particle
fut=future inflection

At one stage, I said that in active sentences, the tense inflections went
on the subject; otherwise, they went on the verb. However, it occurs to me
that this is incorrect: sentences without direct objects have the
inflections on the verb:
   Tai     beimpe ivalle.
   (part.) door   fut-close
   `The door closes.' or `The door is closed'.

   Tai     lein   jafwe.
   (part.) man/it fut-give
   `A man gives.' or `It is given'.

but

   Tai     laan-i valle beimpe.
   (part.) I-fut  close door
   `I close the door.'

   Tai     lein-i  afwe lein.
   (part.) man-fut give it
   `A man gives it.'

   Further, when the verb gains a third valent (i.e. an indirect object),
the tense can be marked by a particle, but this is not obligatory; it can
be marked on the subject as before.

   Tai     lein-i  afwe lein lain.
   (part.) man-fut give it   to you
   `A man gives it to you.'

   Tai     lein ai    afwe lein lain.
   (part.) man  (fut) give it   to you
   `A man gives it to you.'

Either way, any adjectives modifying the subject still agree in tense to
the rest of the sentences.

   Tai     lein-i  mingngka-i afwe lein lain.
   (part.) man-fut strong-fut give it   to you
   `A strong man gives it to you.'

   Tai     lein mingngka-i ai    afwe lein lain.
   (part.) man  strong-fut (fut) give it   to you
   `A strong man gives it to you.'

   What kind of happening is it that I have here? (The situation came up
through use, not planning.) Is it, as I suspect, the way of marking
valencies? Is it a bit of ergativity? Is it completely and utterly stupid
and worthy only of being scrapped here and now? Are there any other
languages that have something similar?

   (And if you're wondering, the ambiguity between `man' and `he/she/it' is
generally solved by the use of a near-obligatory adjective, `vaa', after
the `man'.)

Tristan