1、Recently, the problem of … has aroused peoples concern. 最近,……问题已引起人们的关注。

2、The 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中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、Nowadays, (overpopulation) has become a problem we have to face.

如今,(人口过剩)已成为我们不得不面对的问题了。

4、It is commonly believed that … / It is a common belief that … 人们一般认为……

5、Many people insist that … 很多人坚持认为……