o pleez i hop nut!
I write for a living, but the truth is that *everyone* makes errors, and unless you are blessed with a good proofreader, some will make it into your finished work. I will say that if a Hub or comment is really poorly written, I first check to see if English is obviously a second or maybe third language for the author--if their Profile lists them as living elsewhere than the US or Britain, for example. But if the writing simply seems sloppy I will stop reading at that point.
I mean, there is a spellcheck function almost everywhere on HubPages, so just a quick reading before you click 'submit' should help a lot. However, all languages are fluid, morphing things; a certain amount of creativity is okay as long as you get your point across.
However, not everyone is so understanding, and if enough people vote your Hub or comment down, I would imagine The Gods of Hub will notice and it might very well affect your overall Hub score.