1、nowadays（overpopulation）has become a problem we have to face.（现今，人口过剩已成为我们不得不面对的问题）
2、internet has been playing an increasingly important role in our day-to-day life. it has brought a lot of benefits but has created some serious problems as well.（互联网已在我们的生活扮演着越来越重要的角色，它给我们带来了许多好处但也产生了一些严重的问题）
3、with the rapid development of science and technology，more and more people believe that……（随着科技的迅速发展，越来越多的人认为……）
4、it is a common belief that……==it is commonly believed that……（人们一般认为……）
5、a lot of people seem to think that……（很多人似乎认为……）
6、it is universally acknowledged that + 句子（全世界都知道...）