Ehh, freddie, Iґm sorry to have left for so long
Let's see what I can say here.
Yes, Russian has "leto" for "summer." Year is "god," and it declines regularly except in the genitive plural, when it becomes "let" - so you say "mnogo let" for "many years," or "pjat' let" for "five years," but for one and two you have odin god and dva goda. Iґm guessing that it came from "leto" (five summers ago = five years ago) but I don't really know.
Adj. in Russian added is in gen. as well, but the thing is that the adjective is always in gen. pl. for all numbers except one even if the noun is in gen. sg. (like for dva goda). Except in fem. when the genitive singular of the noun is the same form as the nominative plural like I mentioned. I think technically it MIGHT be OK to say "dve xoroshix (genitive plural) knigi" instead of "dve xoroshie (nominative) knigi" for "two good books," but nobody does.
freddie, I think you got most of what I meant
Iґm kind of confused as to how it works in Slovene though...is ljudi in pet dobrih ljudi the same as nominative? In Russian the adjective is always in genitive plural except for 2, 3, and 4 for feminine nouns that decline regularly. Does Slovene have different rules? It looks like a lot of the same (e.g., Eno dobro leto, dve dobri leti, pet dobrih let) but I'm kind of lost with your last example
