用于解釋性和闡述性論說文
　　1.Everybody knows that…
　　2.It can be easily proved that…
　　3. It is true that…
　　4. No one can deny that
　　5. One thing which is equally important to the above mentioned is…
　　6. the chief reason is that…
　　7. We must recognize that…
　　8. there is on doubt that…
　　9. I am of the opinion that…
　　10. This can be expressed as follows;
　　11. To take …for an example…
　　12. We have reason to believe that
　　13. Now that we know that…
　　14. Among the most convincing reasons given, one should be mentioned…
　　15. the change in …largely results from the fact that
　　16. there are several causes for this significant growth in…,first …,second …,finally…
　　17. A number of factors could account for the development in…
　　18. Perhaps the primary reason is…
　　19. It is chiefly responsible of…
　　20. the reasons for…are complicated, And probably they are found in the fact…
　　21. Here are several possible reasons, excerpt that…
　　22. Somebody believes/argues/holds/insists/thinks that…
　　23. It is not simple to give the reason for this complicated phenomenon…
　　24. Different people observes it in different ways.