Recently, I tend to stumble a lot over the mistake that people write should of instead of should have:
I should of done that.
I am trying to understand what the cause of this confusion between have and of could be. As from a grammatical point of view, I could not think of anything more different than a verb and a preposition. And when I read it, it doesn't even sound the same to me.
So I wonder, is it a regional thing? That somewhere 'have' and 'of' are pronounced the same way? Or is it mostly a common mistake of non-native writers?