All over the world
>animals are killed by people for food.
Może lepiej napisz to zdanie w active voice?
Shouldn't we kill animals for
>food?
>Most people don't think so, becouse meat tastes good.
Coś tu jest pomieszane. Czy nie powinniśmy zabijać zwierząt? Wiekszość ludzi tak nie uważa...
Ja bym to zmienila na: Should we stop killing animals for food? Most people don't think so because.....
Scientists, too, think that we should eat meat. Przecinki *chyba* tak mają być, w każdym razie na pewno nie przed "that".
They're of the opinion tahat the
>animal's meat conteins many proteins and we really need it.
They're of the opinion that meat contAins many proteins that we really need.
On the otherhand we
>knows that vegetables conteins manyy proteins too and we can eat only
>vegetables.
On the other hand we know that......so we could get all our proteins from vegetables only.
Może lepiej będzie pisać bez skrótow: they are, I am, itd.