STUDENTS! Here are three words that don't have an "a" in them:
definitely (not "definately")
independence (not "independance")
persistence (not "persistance")
Please don't make me pull my hair out. Make an effort to check your spelling. Don't do the sloppy thing and assume you're spelling correctly-- especially if you have a history of poor spelling. My own analogy for this sort of mental slovenliness is that of the litterer: a person who litters thinks to himself, "Meh... someone else'll come along and clean up my mess." And so he keeps right on littering, thereby demonstrating laziness and a lack of pride. By the same token, many people who fail to check their own spelling think to themselves, "Meh... I'll get a proofreader to look over my work. What are a few misspellings, after all?"
Don't be sloppy. Take pride in your work.
More language rants on the way.