When do I use "he ovat" and when do I use "ne ovat"?
"He" about people, "ne" about everything else, including animals.
"Ne" can also be used about people, just like its singular variant "se".
True, but only in the spoken language, never in formal text.
So like *hän / se", only plural, yes?
(I'm slow; I only just connected this. Blame the hayfever meds.)
I'm not sure if I understood your question, but:
Hän and he are used about humans; se and ne about anything else. Only in the spoken language it's okay to use se and ne about humans as well.
Why does "nyt" comes first when in the sentence it "now" is at the end of it? Thanks
Because English has a strong tendency to place time adverbials at the end of the clause. Finnish does not share this feature.
Is it okay to omit He here? Or is not implied since we can also create the same sentence with Ne?
Third person pronouns are hardly ever omitted. The subject of a clause with a third person verb can also be any noun.