文章主体句式(Body)：

一、原因 结 果

例：There are probably +[many/several/three]+[reasons/causes]+ for this +[dramatic/marked]+[increase/decline/change]+ in...

二、比 较 对 照

例：[There is no doubt that/Obviously,]+ it has [its/both]+[drawbacks/disadvantages/negative effects]+[as well as/and]+[merits/advantages/positive effects]...

三、例 证

例：We may +[cite/quote/mention/take/point out]+[a single/a common/another]+ example of...

四、事 实

例：

No one can +[deny/doubt/ignore/overlook]+ the +[bare/hard/essential/profound]+ fact that...

五、数 据 调 查

例：

A+[recent/new/nationwide]+[study/survey/poll/investigation]+[conducted/taken]+[at a factory/by officials]...

六、权 威（专 家）

例：

As one +[scientist/writer/doctor/psychologist]+[wrote/commented/pointed out/noted], ...

七、分 析

例：

It seems +[quite/almost]+[(un)likely/(im)possible/(in)credible/(in)conceivable]+ that...