I keep seeing the use of "off of" when "off" is enough. Today, I found it in the operating instructions for my lawn mower, and I see it in the paper from time to time. Once recently, I saw in it a magazine. In this area it is common in speech.

That instruction manual even used "due" instead of "do," but that may be someone translating from one language to another. Usually, it's Japanese or Chinese to English, and English is the translator's second language.

I also notice confusion between "sale" and "sell." A columnist did that in a recent column that ran in the Knoxville paper. I also see it on signs and in classifieds. They say "For Sell," or "Must Sale." I wonder if that is a regional thing.
Howard