阅读下面短文并回答问题，然后将答案写到相应的位置上（请注意问题后的词数要求）。
Today, millions of people want to learn or improve their English, but ‘it’ is difficult to find the best method. Is it better to study in Britain or America or to study in your own country?
The advantages of going to Britain seem obvious. Firstly, you will be able to listen to the language all the time you are in the country. You will be surrounded completely by the language wherever you go. Another advantage is that you have to speak the language if you are with other people.
On the other hand,               of staying at home to study. You don’t have to make big changes to your life. As well as this,it is also a lot cheaper than going to Britain.
So I think that if you have enough time and enough money, the best choice is to spend some time in the UK. But this is not possible for most people, so the most important thing to do in this situation is to catch your opportunities: to speak only English in class and to try to use English whenever possible outside the class.
What is the text mainly about?（no more than 10 words）
                                                                      
Please complete the sentence according to the the passage. (no more than 3 words)
The English language will surround you completely ____________________.
Fill in the blank in Paragraph 3 with proper words. （no more than 8 words）
                                                                      
What suggestion does the author give to those who learn English in their own country?（no more than 15 words）
                                                      
What does the underlined word ‘it’ in paragraph 1 refer to ?(no more than 5words).