What my English teachers told me in 9 years was totally USELESS.

I did only learn the famous OXFORD English, which is just spoken by Mr. Blair and Thames Elly and I did never learn, how to order breakfast, lunch or dinner in a US restaurant. So per coincidence I survived on my first trips (Lucky, those were only a few days long ) and practice helped me to get better in things I need on a daily base, BUT NO TEACHER EVER TOLD ME.

So, nice you had a "kaputt" English teacher, good for him and good for you. ^