Improve oral English

The best way to improve oral English is to leave the circle, in which people only speak their mother tongue. For example, when I came to Canada at the first time, all of my roommates were from China. Undoubtedly, you wouldn't feel lonely living in such environment, however, it was also exploiting you the chances of adapting the Canadian culture. As time went on, you were gonna find your social circle was becoming smaller and smaller and you even didn't speak English all day except some pathetic greeting words, such as "Whats up" or "Bye". It was gonna ruin your life in Canada if this thing persisted.