Normally, one studies in the language of the country in which they are attending school.
If the course is taught in English, they would require proof of a certain level of ability in that language. I think Jig would need to have a higher level of written English than we see in this thread, however when writing an essay, I suspect most people would take more care with grammar than they would just posting on some internet forum.
And Dominicb 's intention is that he does not support anyone coming to Poland
From certain countries yes. Basically he came here and it didn't work out for him.