（七）开篇
1） Many nations have been faced with the problem of ...
2） Recently the problem has been brought into focus.
3） Recently the phenomenon has become a heated topic.
4） Recently the issue has aroused great concern among ...
5） Nowadays there is a growing concern over ...
6） Never in our history has the idea that …… been so popular.
7） Faced with ……, quite a few people argue that ...
8） According to a recent survey, ...
9） With the rapid development of ……。.