第一：宾语从句
Eg: Some people claim that government should be mainly responsible for the environmental pollution.
一些人认为政府应对环境污染负主要责任。
第二：状语从句
在托福写作当中运用的最多的是以下五种状语从句，即原因状语从句，让步状语从句，条件状语从句，时间状语从句和目的状语从句。
1.原因状语从句
常由because, as, since和for引导。
Eg: Nonetheless, I am still in favor of space travel, for its merits far outweigh demerits.
尽管如此，我还是赞成太空探险，因为它的好处远远大于坏处。
2.让步状语从句常由although, though, even though/ if, as long as和not with standing引导
Eg: Although this view is wildly held, this is little evidence that education can be obtained at any age and at any place.
尽管这一观点被广泛接受，很少有证据表明教育能够在任何地点、任何年龄进行。
3.条件状语从句常由if, on the condition that和providing that引导
Eg: If you want to achieve something or intend to fulfill one of your ambitions, you must work hard, make efforts and get prepared.
假如你要取得成就或要实现你的雄心壮志，你必须努力工作、艰苦奋斗、准备好条件。
4.时间状语从句常由when和while引导
Eg: When it comes to education, the majority of people believe that education is a lifetime study.
说到教育，大部分人认为其是一个终生的学习。
5.目的状语从句常由so that和in order that引导
Eg: Millions of people have to spend more time and energy on studying new skills and technology so that they can keep a favorable position in job market.
成千上万的人们不得不花费的精力和时间学习新的技术和知识，使得他们在就业市场能保持优势。
第三：同位语从句
Eg: It is cars and factories that release a great deal of gases, polluting the environment.
汽车和工厂排放大量的废气，使得环境被污染。
第四：主语从句
Eg: What has caught our attention is /It is noticeable that the environment in both the rural and urban areas is deteriorating.
值得注意的是农村和城市的生态环境都在不断恶化。
第五：定语从句
最常用的一种句型之一。适当地运用定语从句可以给你的文章增色不少。例如，下面的这两个句子用上定语从句马上就变成了一个漂亮的复杂句。
Bad books contain evil thoughts. In them, there might be much description about violence, superstition, and sex.
改变后：Bad books, in which there might be much description about violence, superstition, and sex, contain evil thoughts.
第六：强调句
It is + 被强调的内容 + thatEg: It is cars and factories that release a great deal of gases, polluting the environment.
汽车和工厂排放大量的废气，使得环境被污染
第七：倒装句
Eg: Only if the government will take some appropriate measures, will this intractable problem be tackled.
只有政府采取适当的措施，这个棘手的问题才能被解决。
第八：被动语态
Eg: Every means should be tried to protect the environment on which people live.
人们应竭尽全力来保护我们赖以生存的环境。
第九：分词结构
包括现在分词和过去分词。
Eg: Tourism, which is a rising industry, has become the ma
旅游业是一个新兴的行业，它成为经济的主要在很多东南亚国家起着尤为重要的作用。
第十：插入语
一种独立成分，与句子的其它成分一般没有语法上的关系。大都是对一句话作一些附加说明或解释。它通常由一个词、一个短语或一个句子构成位置较为灵活，可置于句首、句中或句末，一般用逗号或破折号与句子隔开。
Eg: Computer, an indispensable part in our life, has brought us great conveniences.
电脑，我们生活中必不可少的一部分，给我们带来了极大的方便。
托福写作, 高频