Spent two years in Germany courtesy of US Army. Two local siblings (girl and boy) hung out with us some nights at a local bar. Both spoke very good English. She was attending University in a program that prepared her to teach English in the German school system. She learned the English straight out of the book in class. Our slang and accent depending on which parts of the states we were from invariably through her off and needed clarification. Everything does not translate from language to language.