At the time of my secondary school, because of nothing teachers graduated from English at their university, they did not know to teach students a method how to learn English. It was very frustrated. The passing rate of English language in HKCEE only reached 40% and included most of grade in D or E.
Since I started my jobs, I have found that my English standard cannot afford daily use. It led me to abandon contact English.
Anyway, for key to success in learning English, in my mind, only your mind is whether or not determinative. Next, whether or not you can find out suitable textbooks for your study and reference. Fortunately, after completion of my undergraduate, I am able to select the books in learning English.
I am of view that if you want to improve your English, then you must learn the grammar rules. Your construction in oral or writing will be improved and better than before. Watching DVD and following their English subtitle are also crucial to beginners.