I agree with HUAYUE, if you want to learn the language well, you can go to the original language country, it is the best environment for you to learn it.
But it is a pity that not everyone have the enough money and time, or chance to go to the original language country, so we must study it hard by oursleves without the best environment. We just often listen to the tape, talk with some foreigner on-line, or write some artical to improve, etc.