4. 介紹當前背景、現象、形勢+介紹雙方觀點+說出自己的觀點
例1：
the problem of traffic jams in big cities is very common in developing countries and china is of no exception. as how to solve this problem, people hold different opinions. some suggest that in china, we should give priority to the development of private cars, but others argue that public transportation should be put in the first place. i am for the latter.