The standarts of the languages. As for me of couse it's easily to argue about Russian. But it' common problem. For example Italy had historycal, cultural and linguistic division on French and Italian parts. And the country became united by national press only. After its appearence people from diffirent provinces had to read and understand one common form of language. Russia is a very big country with one state and plural national languages. That's why in diffirent regions we can hear diffirent dialects of Russian. But the standart of prononsciation is moscowite dialect. It's used on central TV chanals. If a foreghner wants to speak correcly, he should learn it. So... weather people from other Russian regions or Russian-speaking countries could be teachers of speaking language? In a book of Maria Arbatova there is a story about Nigerian speaking Russian with Georgian accent. Really, it's very funny!!!! And, at the end: what form (variant, accent, dialect) of the English is the most correct?