There's a very important insight to be had by reflecting on the following English sentences and noticing the implied quantifiers:
"Trees are green." - implies a generalization; most if not all trees.
"Teenagers did this." - implies only some group of teenagers, not all of them, not even a majority.
"Humans have 10 fingers." - generalization.
"Customers are here." - just some.
"Humans have the MacGuffin." - interestingly, not a generalization; it only means the MacGuffin is possessed by humans.
"Humans have 10 MacGuffins." - seems to mean that all the humans collectively have 10 MacGuffins, but not each one individually; interesting how this differs from the 10 fingers case.
So English, with an omitted quantifier, allows as interpretations
Japanese is an even more interesting case. Since Japanese has no word for "the", and its general philosophy is "leave out as much as you can to infer it from context", often an unqualified noun in Japanese conveys the meaning of "the". Although, I'm pretty sure Japanese would also express the English "
I've thought a lot about what Spem should do as a default; my current belief is that
mi kei kotu- most likely "I have (some) book(s)", but potentially "I have the book(s)". ɑn, ɪl ɪv lɪmɵl, (but) mi nu keni- "He wanted water, but I didn't give (it)." ŋi nu gu kei, θo ŋi ʌ sutu.- "You don't give (anything), and that makes you selfish." Okay this might be a bad example because maybe that should've been expressed as gu kei neminstead of nu gu kei. Or maybe not because that can be interpreted as gi kei yɪm. I don't know. There's still a lot to think about.