2. It is generally /usually accepted /agreed/recognized that ----普遍认为

　　3. It is believed that -----有人相信

　　4. It is well-known that ----大家知道

　　5. It is said that ----据说

　　6. It is learned that ---据闻

　　7. It is supposed that----据推测

　　8. It is estimated/predicted/calculated that---据估计

　　13. It will be seen from this that ----由此可见

　　14. It is understood that----不用说

　　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