"They are cats."

Translation: Αυτές είναι γάτες.

[LIQUID_INFERNO]

Anywhere I can read about the rules that make this thing happen "αυτές-γάτες", "αυτοί-γάτοι"?

[ChemicalWa1]

Why is this not, Αυτοί είναι γάτες

[Sotirios]

Because they don't match, one being female (γάτες) and the other male (αυτοί)

[vale_221096]

I understand that αυτές here is because γάτες is feminine plural, but what if we see some kids (παιδιά, neuter plural) at a costume party and they are dressed up as cats?

Would it be correct to say "Αυτά είναι γάτες"? Or maybe even "Αυτοί είναι γάτες", if some men are dressed up as cats. Or even weirder; say two kids are in a big shared costume of a cat in which the two can fit in, and one gets to be the left side and the other one the right side. Could this be "Αυτά είναι μία γάτα", since the two kids are dressed up as one cat? Would these sentences be acceptable and correct in such cases?

It may sound silly but in Spanish it actually works haha but I'm no native Greek speaker, so I must ask

[D_..]

Would these sentences be acceptable and correct in such cases?

Yes, all of them are correct in Greek too. :)

[vale_221096]

Thanks a lot!

[AttiDrehto]

Speakers of Greek have to know at the very beginning of the sentence what its last word is going to be. That's really challenging!