Long ago I spent a year in beijing, and there were some africans in the same building, some french speakers, and some english. When the english speakers talked to me or others like me (e.g., same lunch/dinner table), I could generally understand what they were saying. When they talked to each other (in english), I was lost.
Look up Kachru's three circles--inner, outer, and expanding. There are lots of different englishes in the world.