"Mówisz po angielsku."
Translation:You speak English.
Isn't it fascinating how "po angielsku" sounds/feels like speaking "the angels language" =),.. this word was my first impression about Polish and a very strong motivation to try it (besides, I lived in Poland when I was a child, but I was less than 3 years old and I can't rememvber any single word in Polish.. so I have actually been waiting for this course to become available for quite a while already =).
It means either the purpose or reason (why) you are doing something, or the way to do it (in what manner or how you do it), e.g.:
po chleb = in order to get some bread
po angielsku = in english (like in "written in english")
There may be more examples, these are just a few that came to my mind instantly.