1. It is considered /thought that 人们(有人,大家)认为
2. It is generally /usually accepted /agreed/recognized that 普遍(一般,通常)认为
3. It is believed that 有人(人们,大家)相信
4. It is well-known that 大家知道(众所周知)
5. It is said that 据说(有人说)
6. It is learned that 据闻(悉)
7. It is supposed that据推测
8. It is estimated/predicted/calculated that据估计(预计)
9. It must be pointed that 必须指出
10. It is reported that据报道
11. It must be admitted that必须承认
12. It will be seen that 可见(可以看出)
13. It will be seen from this that 由此可见
14. It is understood that不用说(都知道)
15. It can not be denied that无可否认
16. It has been proved/demonstrated that已经证明
17. It may be confirmed that 可以肯定
18. It may be safely said that可以有把握地说
19. It is sometimes asked that人们有时会问
20. It is expected that/hoped that人们希望
21. When it comes to 要说到,要谈及