The importance of learning a language

Rita used these words to express her enthusiasm for Macbeth:
"I thought it was gonna be dead borin'...
But listen, it wasn't borin' , it was bleedin' great honest, ogh, it done me in, it was fantastic. I'm gonna do an essay on it".
Of course, her language is not acceptable to do an essay. In the past, in England class was determined by the way people spoke but even more important was their accent. For example, people with strong accent like Rita's were assumed to be working class while people with RP accent was assumed to be upper or upper-middle class. However, then it was acceptable to speak standard British English in public speaking, radio, TV, books, newspapers, at school and university. That is why she is supposed to learn standard English. She must learn British language and how to use it in certain circumstances, that is in context.