No amount of studying outside of the native environment will give you the skill level necessary to easily maintain social conversations once you're in it.
English is not my native language. However, I went to a school that had a specific emphasis on English: we had 5 hours of it per week in the first three grades, gradually ramping up to 6 in middle school and 7 in high school, and adding English literature on top of that. We wrote numerous essays, listened to recordings of native speakers, and spent a lot of time talking and listening to each other.
Then I went to study in a college in a country where English is a native language. I could read and write easily - better than natives in many cases, in fact (I'll never forget a rant that our elderly ethics teacher gave to me in private about how, based on the essays she was grading, only people with non-Anglo names could spell "its" vs "it's" right consistently). I could also speak fast while remaining perfectly understandable, and showing only a very subtle, hard-to-identify accent - that's where those hours of listening to tapes and talking with other students to polish pronunciation really paid off.
But for the life of me, I couldn't understand half of what people were saying. It was either too fast, or it was in an accent or dialect that was too unfamiliar to parse easily, or it was too casual (shortening or outright dropping many things that are always there in writing); and often, all of these at once. I had to ask people to slow down and repeat things - made all the more confusing because I spoke at a much faster pace (as I was taught to) than what I could follow.
It took about two months for everything to really click to the point where I could follow any conversation, and a lot longer than that before it stopped being a conscious mental effort.
English is not my native language. However, I went to a school that had a specific emphasis on English: we had 5 hours of it per week in the first three grades, gradually ramping up to 6 in middle school and 7 in high school, and adding English literature on top of that. We wrote numerous essays, listened to recordings of native speakers, and spent a lot of time talking and listening to each other.
Then I went to study in a college in a country where English is a native language. I could read and write easily - better than natives in many cases, in fact (I'll never forget a rant that our elderly ethics teacher gave to me in private about how, based on the essays she was grading, only people with non-Anglo names could spell "its" vs "it's" right consistently). I could also speak fast while remaining perfectly understandable, and showing only a very subtle, hard-to-identify accent - that's where those hours of listening to tapes and talking with other students to polish pronunciation really paid off.
But for the life of me, I couldn't understand half of what people were saying. It was either too fast, or it was in an accent or dialect that was too unfamiliar to parse easily, or it was too casual (shortening or outright dropping many things that are always there in writing); and often, all of these at once. I had to ask people to slow down and repeat things - made all the more confusing because I spoke at a much faster pace (as I was taught to) than what I could follow.
It took about two months for everything to really click to the point where I could follow any conversation, and a lot longer than that before it stopped being a conscious mental effort.