Hello,
what do you think about daily English (common language) used by the most of people.
I know a lot of native users using really simple English despite they're are really well educated.
I remember that on iTalki was a topic about translating your own language into English in 1:1. Of course it's a big mistake :)
My question is about how complicated English do you use in everyday life? Probably you will wrote that all depends on your education level, where do you live, what you do for a living etc. :)