How is the life in the environment where people do not speak in your native language? It is one of the most popular question prospective immigrants ask themselves. Usually for families with kids it is more important. I believe that after living almost a year in Canada I can answer to this question. It is really easy! So, take it easy! I will try to go into details and prove my conclusion. Of course all conclusions are based on my own experience. Therefore, each person may have own experience which is different.
First of all when you move to a new country you try to find people who are familiar with your culture, or came from the same country you did. After having some community who speaks same language, you almost loose the need speaking in English with them at all. What happened with me, when I moved to Canada my friend from university met us at the airport. And then he introduced us to other Azerbaijani Turks living in Edmonton. So daily use of English was limited to my work and shopping in Edmonton. Taking into account that most people prefer sending e-mails instead of discussing personally, so I was not using English too much at work. As regard the shopping the only words you need to say is type of the payment card when you are paying for the goods purchased. So, does not look like you are ling in English speaking environment, 90% of your talks are in you native language. I mean in your family, with local friends.
At some point I started feeling that I am not using English in my daily life anymore. It happened after I moved to Calgary. As you aware my boss mmw is Russian. Taking into account that I am almost fluent in Russian we use Russian in our communication. So, what is the picture at the end, I am speaking Azeri Turkish at home and friends, Russian with my boss... Where is English? Rare use of English weakens my speaking. And how I can say that I am living in English speaking country?! Looks like some actions should be taken to prevent degradation of my English.
I remember couple years ago when I watched a documentary about Chinese people living in NYC without understanding English I was really surprised. Now I am completely sure that without having English you may survive in English speaking country!
P.S. One of guys who moved to Toronto 4 months ago also said that he almost forgot English...