I'm not a very good speller or writer (I taught science, not English), but I do know bad grammar when I hear it. And I hear it all the time.
Where I live, I'm used to "he don't", "we was", "ain't", etc. That's part of hoosierism (yes, that word was highlighted in yellow). It still hurts the ears, but I have to accept it. I eventually had to let it go when I was teaching--corrections were hopeless.
But when almost all TV sport announcers say "real" rather than "really" (as in "He hit the ball real hard."), I cringe every time. Weathermen: "It's going to be real cold tonight." Ouch. Substituting the word "very" should tell you if you've misused "real". It drives me crazy.
Another grammatical mistake that bugs me (but doesn't bother me nearly as much) is the use of the plural verb with "none", as in "None of the pears are ripe". That should be "is ripe": Not one (which "none" is a contraction) of the pears is ripe. That's an easy mistake and difficult to correctly say.
One more: split infinitives. "To boldly go where no man..."(Star Trek), or "You are to not watch TV now". The word "to" should follow "boldly" and "not". Reread the last sentence in the last paragraph. Did you notice I split the infinitive? It just sounds funny to write "correctly to say". I frequently make that mistake, so I'm not trying to act that all superior. I'm simply venting in this post.