【导语】英语语法让很多学生都头疼，因为复杂难懂的句式和词组有时难以记忆。英语网为大家整理了英语语法大全，希望对同学们的英语语法学习有所帮助。更多内容尽在英语网。
在许多情况下，当语义上需要用一个较复杂的that从句用主语时，若直接将其置于句首位置，则会显得头轻脚重。这时，我们通常采用的办法便是使用形式主语it来改变句子结构。如：
That he had no girl friends worried his parents a lot.= It worried his parents a lot that he had no girl friends. 他没有女朋友，这件事使他父母非常不安。
That he has fully recovered makes me feel good.=It makes me feel good that he has fully recovered. 他已痊愈，真令我高兴。
That he had not said anything surprised everybody.=It surprised everybody that he had not said anything. 他一言不发，这使大家很吃惊。
用形式主语改变句子结构是许多同学都可能想得到的方式，属通常思维，乃常规表达。但如果借助the fact这一辅助手段，按以下方式改写句子，则会给人以耳目一新的感觉，许多阅卷老师会将其划入高级结构的范畴。如：
The fact that he had no girl friends worried his parents a lot.
The fact that he has fully recovered makes me feel good.
The fact that he had not said anything surprised everybody.