I am reading a series of books about the German language and I came across a concept that sounded totally convincing to me. It was written by Tsugio Sekiguchi, who is well-known among German students in Japan. He is said to be familiar with other foreign languages such as French, Latin, Greece as well as English. He was so excelled at Latin that he was made a teacher of the language at a private school. He said in the book that in order to master a foreign language, you have to do two things: both understanding the grammar, phrases or words and getting accustomed to what you have understood. These two things work in combination. Without either one, you would never master the language.
I couldn't agree more because it is true of my own experience of learning English. I studied grammar books to understand the grammar and read and wrote in English to get accustomed to it.
What I am concerned about is that, as far as I can see, those who think they are skilful enough at English don't think it necessary to learn about the language any longer: "The job is over. We can go." They only try to get more and more accustomed to it. But the understanding part is also important no matter how familiar you are with English. Grab a grammar book and open it, and you will undoubtedly find information which you don't know that you should have known before. Language as I see it is an endless fountain of knowledge.