第一類：表示原因
1)There are three reasons for this/...
2)The reasons for this are as follows:...
3)The reason for this is obvious.
4)The reason for this/... is not far to seek.
5)The reason for this is that...
第二類：表示益處/害處
1) It has the following advantages.
2) It does us a lot of good to ...
3) It benefits us quite a lot.
4) It is beneficial to us.
5) It is of great benefit to us.
6) We have good reasons to believe that...
7) It has more disadvantages than advantages.
8) It does us much harm.= it does much harm to us.
第三類：表示變化
1) Some changes have taken place in the past five years.
2) A great change will certainly be produced in the world's communications.
3) The computer has brought about many changes in education.
第四類：表示重要性
1) Doing sth. is of utmost importance.
2) It plays an important role in our life.
3) It is vital that .../ to do sth
4) Sth plays an essential role/part (in sth).
5) Sth is an essential part of sth.
第五類：表示措施
1)We should take some effective measures.
2) It is high time we tried our best to overcome(conquer)the difficulties.
3) Great effort is needed to…
4) There are several ways to deal with the problem.
第六類：表示事實(shí)現(xiàn)狀（首段常見）
1) We cannot ignore the fact that…
2) No one can deny the fact that…/There is no denying the fact that…
3) indeed /apparently / obviously
4) This is a phenomenon that many people are interested in...
5) It is true that…
6) It is generally admitted that ......
第七類：表示比較
1) Compared with A,，B……
2) I prefer to read rather than watch TV.
3) There is a striking contrast between them.
第八類：表示看法（首段或尾段）
1)People have(take，adopt,，assume)different attitudes towards sth.
2) From my point of view ...
3)People take different views of(on)the question.
4)Some people believe that…Others argue that…
5)In terms of money, it’s a great job.
（有道考神）