考研四级句式包括以下几种：
列举原因
Three major reasons that account for such a phenomenon are listed as follows.
This phenomenon exists for a number of reasons. First… Second… Third…
强调重要性
There is no doubt that…is going to be the biggest problem for…
We cannot emphasize the importance of balanced diet too much.
无可否认的事实
There is no denying the fact that people’s living standard has been greatly elevated over the past few decades.
倒装句
Under no circumstances can/shall we+ V.
Seldom does he play basketball because he is busy with his studies.
Not only+助动词+主语+部分谓语+其他部分.
比较句
Nothing is more important than to receive education.
The merchant as good as promised the orphan boy, that he would adopt him.
表明观点立场
For my part, I agree with the latter opinion for the following reasons:
引出现象
It is indisputable that technology has dramatically changed people’s life.
条件句
If/whether + 主语 + 过去式/情态动词 + 其他
这些句式在考研作文中非常常见，掌握它们可以帮助考生更好地理解和表达英语语言，提高四级考试的得分。建议在写作时根据具体的写作场景和需要选择合适的句式，使文章更加流畅和有力。