(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 ...
