Brush up English. Approximately 20 years ago, I went to Canberra, Australia to take an intensive English language course. Approximately 20　years　ago,　I　went　to　Canberra,　Australia　for　the　purpose　of　taking　an　intensive　English　language　course. Approximately 20 years ago, I went to Canberra , Australia with an aim to taking an intensive English language course. Approximately 20 years ago, I went to Canberra, Australia with a view to taking an intensive English language course. Approximately 20 years ago, I went to Canberra, Australia so that I could take an intensive English language course. Approximately 20 years ago, I went to Canberra, Australia in an effort to take an intensive English language course. Among above English sentences, which is the most suitable for speaking or writing? It is essential that I should study English very hard. It is indispensable that I should study English very hard. It is necessary that I should study English very hard. I need to study English very hard. I have to study English very hard. I must study English very hard.