Finally something useful!
кошки sounds pretty funny when played just by itself.
Why is it they're and not their?
Because they're is a contraction of they are, and their means "belonging to them". They aren't synonymous.
Они кошки means they are (they're) cats. Their cats (the cats that belong to them) would be их кошки.
"Кот" means male cat and "кошка" female? Idk °^°
Does that sentence have another conotation? In portuguese, if you call someone a cat it means the person is beautiful
Kind of. It just isn't exeptionaly common.
Why is они кошки (no cap, no full stop) wrong and why is there no "my solution should be accepted" option?
Они не собаки?