Quote Originally Posted by Philipvs Vallindervs Calicvla View Post
I don't think this is true, if you have a basic grounding in a language (very basic) and are then immersed in the culture and forced to speak it every day you will reach fluency somewhere between 6 months and a year. If this was not so we wouldn't be able to send in English students to France or Germany and dump them into the Universities there, which we do.
For the immigrants who do not learn the language: they are not immersed in the culture, nor forced to speak the language every day. Otherwise they would learn it.
For the rest there is more to a language than being able to do shopping, day to day communication etc. You become fluent in a subset of it, but not necessarily competent with the whole framework of syntax, grammar, idiom etc.