There are two pre-requisites for learning any language: interest in the language and willingess to exposure of that language.

Interest is somehow similar to motivation. If you are not interested or, say, you are not motivated you will not learn a language even if you live for a thousand years within a community where that language is the only one spoken.

The level of interest differs from person to person. Some people just need to learn the language to be able to get along with daily activies. Such people obviously have a low level of interest. Others want to learn it more so that they can apply for a job or can have an occupation where the language is required. Obviously these people have to have more interest in the language. Finally, some people just love the language--- for the heck of it! And it is these people who are most interested in the language.

The second, but not secondary, requirement of learning a language is exposure. No exposure, no learning. You need to expose yourself to different linguistic situations in order to learn. A complete description of this topic is beyond the scope of this discussion. Suffice it to say you should listen to the news, listen to other people talk, read and write the language. You should speak it, think it, eat it, drink it, feel it and, I say touch it. Then will you master the language, English or any otherwise.