The o vowel of future-tense -os plus the nt of the Latin/Romance active present participle.
- (agentic substantive) -onto Nominative do'er of an action, in a future relative to when the corresponding verb took place.
- (adjectival participle) -onta Characteristic of doing an action, in a future relative to the verb. (active future participle)
- (adverbial participle) -onte In a way characteristic of doing an action, in a future relative to the verb. (active future adverbial participle)
Even if the word takes the accusative form (e.g. amonton or amontan), the word forms a substantive or adjective as-if a nominative for the participle's root.