The fact is, how do we know they are typos? I was curious, and I just tried to look of "if you have chance" on myspaces, and there are very few compared to "if you have the chance", etc., but still, there are some. And many of them come form native speakers, mainly form the UK, or so it seems... because, what do you know about those people? Maybe they are
immigrants, maybe those were just typos, maybe it's a rare form in a rare dialect, maybe they are just dorks... but maybe they meant to write it that way, indeed.
Or maybe it's an accepted form in the spoken English of quite a few Brits - Mr P excluded. Now why didn't you think of that?
I didn't know about it, it seems a new one, and it might be very useful... I'm going to try it out.

If you do try it out and you have comments about it, Mark Davies would love an e-mail from you. He does respond. Clever guy, and one to watch.
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