"The cats are white."

Translation: Katterna är vita.

[Tysim6]

I typed "Katterna ar vit" i
I see that some time's it's vita and vit so i'm wondering how I will know what one I use for the sentence.

[Zmrzlina]

Plurals get the -a, thus it's vita here.

[makmegs]

Does that apply to all other colours?

[Zmrzlina]

Generally it applies to all adjectives. Some colors are special though. Rosa (pink) and lila (purple) never change, for example.

[abhinaybyrisetty]

Thanks Zmrzlina :)

[Anoma260581]

And when is 'vitt' used?

[Gray_Roze]

After studying German and Dutch, where adjectives don't decline after a linking verb (i.e. "Die Katzen sind weiß" and not "Die Katzen sind weiße," "De katten zijn wit" and not "De katten zijn witte"), it's going to be hard to get used to declining them in situations like this.

[D_bigFreD]

Thanks guys, you are made it more clear to me