Sorry if I sound negative about this thread, but I consider this cheating. Especially if the essay is for an English lesson.
i disapprove of this topic considering writing ability is measured solely by the writer's writing abilityI don't want to be insulting to either of you, but if you're at a level with your writing where the primary assessment is on it's quality, not it's content, then just stay out of this thread. In any case, if having a second person proof reading your English essay is going to be considered cheating by whomever is marking it, then it's upto you not to have it proofread. Simple.
I think you both have some misconceptions about what proofreading actually involves. It's simply checking for errors, in both spelling and grammar. I find it usually extends beyond that into looking for inconsistency in your writing style and most people have suggestions on better wording for readability, but those are editing issues.
There is very little written work that should not be atleast proofread, if not edited with someone else.