Kyo Sohma
He is the cat. (which isn't an actual zodiac sign)
he is the cat but the cat isn't really part of the zodiac
Ritsu Sohma from Fruits Basket is the monkey of Zodiac.
In "Fruits Basket," Kagura is the boar of the zodiac.
He is the cow/ox.
Well, the rat and the cat hated each other from the start because of this story: God invited all of the animals to a banquet but the rat told the cat that it would be a day after when it actually was, so the cat slept through the whole thing. So the cat wouldn't be able to be part of the zodiac all because of the rat.
In the story of the Chinese zodiac, the animals would meet to be part of the zodiac. The rat tricked the cat by telling him the meeting was the day after. So the cat stayed home not knowing of the trick. That is why the cat is not part of the Chinese zodiac.
Kureno Sohma is the bird of the zodiac
They don't have to be born in the year of that animal in order to embody or represent the animal they have. E.x. Kyo is born in the same year as Yuki, though they do not represent the same zodiac animal.
Fruits Basket
Nope
yep. the banquet part is.