On topic, Animal Crossing taught me English! I'm not a native speaker. When I started playing ACWW, I was 10 years old and I didn't understand a thing, but through the years it has definitely helped me learn the language. And the bugs and fish of course as well.
Oh, wow! That's quite a feat! It truly is a great game, isn't it ;v;
I'm also not a native speaker, and games, tv shows and etc. definitely helped me, but sadly not AC, as I only started playing this year.