Why is it that x Why is that: Qual a diferença

Existe diferença entre it that e that?

Nas frases abaixo, alguma está errado:
Why is it that we study other animals instead of them studing us?
Why is that we study other animals instead of them studing us?

Pelo que entendi, usa se o "it" para não deixar a frase sem sujeito, porém há sujeito nesta frase. Por que "it that"?

Alguém pode me ajudar por favor.
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Avatar do usuário PPAULO 45265 6 35 800
Why is it that we study other animals instead of them studying us?

Is the correct one, the "it" is needed, and you forgot the letter y in "studying".

como-dizer-por-que-sera-que-em-ingles-t2745.html

"Why is that" could be used in a isolated way, though:
-Do you have a bank account?
-No
-Why is that?
What is it that makes you you is different of What is that makes you you?
Avatar do usuário PPAULO 45265 6 35 800
What is it that makes you you is different? It needs an elaborate answer.
To the second, one could ask "what makes you different (from others, etc...)?".
Avatar do usuário Marcio_Farias 12500 1 23 210
I'd settle for "What makes you..."
Avatar do usuário PPAULO 45265 6 35 800
By the way, a little correction on my answer:
What is it that makes you different? (no double "you" and no "is" in the sentence).