二、中間段
中間段是文章的正文，其作用是從不同的層面對文章主題進行具體和詳實的解釋和論證。
1、中間段的一般特征
① 篇幅一般比開頭段和結尾段長。
② 每段有相應的主題句。
③包含定義、解釋、描寫，說明主題思想的擴展句可以采用實例、數據或個人經歷等寫作手段。
④不同種類的段落采用不同的擴展手段。
2.中間段的常用核心句型：
1.Although the popular belief is that…， a current (new / recent) study (survey / poll / investigation) indicates (shows / demonstrates) that…。
2.Common sense tells us that…。
3.The increase (change / failure / success) in…mainly (largely / partly) results from (arises from / is because of)…。
4.The increase (change / failure / success) in…is due to (owing to / attributable to) the fact that…。
5.Many people would claim that…。
6.One may attribute (ascribe / owe) the increase (decrease / change ) to…， but…is not by itself an adequate explanation。
7.One of the reasons given for…is that…。
8.What is also worth noticing is that…。
9.There are many (different / several /a number of / a variety of)causes (reasons) for this dramatic (marked / significant) growth (change / decline / increase) in…。 First，…。 Second，…。 Finally，…。
10.There is no evidence to suggest that…。
11.Why are (is / do / did)…？ For one thing，…。 For another，…。
12.Another reason why I dispute the above statement is that…。
13.It gives rise to (lead to / bring /create) a host of problems (consequences)。
14.There are numerous reasons why…， and I shall here explore only a few of the most important ones。
15.It will exert (have / produce) profound (far-reaching / remarkable / considerable / beneficial / favorable / undesirable / disastrous) effect (influence) on…。
16.A multitude of factors could account for (contribute to / lead to / result in / influence) the change (increase / decrease / success / failure / development) in…。
17.In 2000， it increased (rose / jumped / shot up) from 5 to 10 percent of the total (to 15 percent / by 15 percent)。
18.By comparison with 2002， it decreased (dropped / fell) from 10 to 5 percent (to 15 percent / by 15 percent)。
19.It accounts for 15 percent of the total。
20.There were 100 traffic accidents in April， an increase of 5 percent in a five-month period。
21.By 2002， only (less than / more than / almost / about / over/ as many as) three quarters (40 percent of / one out of five / one in four) college population (graduates / housewives) as against (as compared with) last year (2002) preferred to (liked)…。 22.With the development (improvement / rise / growth / general recognition / acknowledgement / realization) of…， vast changes awaits this country‘s society。
23.Now people in growing (ever-increasing / significant) numbers are beginning (coming / getting) to believe (realize / recognize / understand / accept / see / be aware) that…。
24.According to a(n) recent (new / official) study (survey / report / poll)，…。
25.History (Our society) is filled (abounds) with the examples of…。
26.The story (case / instance / situation) is not rare (isolated / unique)， it is one of many examples (typical of dozens)。
27.A (one) recent (new / general / nationwide) study (survey / poll / investigation) conducted (taken) at a university by (officials / scientists / experts) indicates (reveals / suggests / shows / proves / demonstrates) that…。
28.According to (As can be seen in / As is shown in) the figures (statistics / findings / data / graph / table) released (provided) by the government (an institute)， it can be learned (seen / predicted) that…。
29.There is (no) good (every / little / sufficient / considerable / strong) evidence (proof) to
30.Personal experience (Examples I heard / read of) leads me to conclude that…。
31.We must admit the undeniable fact that…。
32.No one can deny (ignore / doubt / overlook / obscure / brush aside) the fact that…。
33.Experience (Evidence) suggests (shows) that…。
34.Take for example…who (that)…。
35.The same is true of…。
36.As the saying goes，“…。”
