'Everyone who doesn't cook their food'
Is it correct? If it's correct then can you explain why do we use doesn't but the possessive pronoun is Their?
'Everyone who doesn't cook their food'
Is it correct? If it's correct then can you explain why do we use doesn't but the possessive pronoun is Their?
It is not really correct. Some word houses say that third person possessive is ok in general, and so much so for "mass nouns" like everyone (That is, although it is referring to "one" person, it is referring to every "one" of those persons...). I agree for speech.
It writing, I adopt parallel construction (really just conjugation)
This kind of tool is convenient to Everyone (of us) who does not cook his food
I believe "he," like "man," is gender neutral in this use, as meaning is of course contextual. You could add "or her" (though I would prefer to interchange).
This kind of tool is convenient to Everyone (of us) who does not cook his or her [xir] food