Disclaimer: I have this delima with people who have at least a C1. I also know that the obvious answer to my problem is to watch my language but when I'm with a close friend I sometimes use wrong grammar that I would use with a native speaker.

I believe that everyone has a personal dialect. There is not just one dialect. For example, I say "cool beans", "that's a bop", "I got fixins", "that's lit", and so forth.

My "personal dialect" also uses incorrect grammar. The three that I can think of right now are:

1) I love me some ___________. Ex. I love me some chicken.

2) There ain't no nobody that _______ Ex. There ain't no nobody that can run a 2 minute mile.

3) Y'all and y'allsses Ex. Do y'all got y'allses rooms clean? (I'm the only person I've ever met who says y'allses)

When I make these mistakes with a friend that is a non-natve English speaker I correct myself and say, "Don't say that. That's bad grammar".

I believe that we learn phrases by imitating phrases. I know that I would be frustrated if I learned a German phrase and then learned that it was wrong grammar.

Here's some questions that I would like to ask you all.

1) Do you also experience this issue?

2) How would you feel if you were talking with your friend and they stopped and told you that they just used bad grammar in their native language?

3) Would you care at all?

4) Is there a better way to deal with this issue than just saying "Don't say that. That's bad grammar".

Thanks!