Cats may not exactly be human, but cats are what makes us human.

No, no, no! When I put 'sono umana' for 'I am human', I get told the only correct answer is 'sono umano' (I've 'reported' it), but suddenly for 'the cat is not human', both 'umano' and 'umana' are correct?! I'm aware that there are female cats, I have one myself, but then surely it would be 'la gatta' anyway, no? I am so confused, help!

I think somebody with good and better knowledge of Italian should comment and explain whether and why this is correct. Until then I agree with your comment and consider your answer correct.

il gatto non è umano, anzi il gatto è meglio di umani.

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