大学英语四级考试涉及的语法知识点多、涉及面宽，对不少考生来说都是一个难题。希望通过本文的学习，考生能对四级语法有更全面的掌握!

　　部分倒装的形式: 主谓宾保持原来的形式，谓语动词的助动词放到主语的前面。

　　1、当句首状语为否定词或带有否定意义的词语时，这个句子就需要部分倒装。

　　这类词语有hardly, scarcely, rarely, seldom, never, few,little, less, at no time, by no means, in no case, under no circumstance, in no way,on no account, on no consideration, no longer, not only等。

　　eg. He never smokes. 他从来不抽烟。

　　Never does he smoke. eg. Not only did the customer complain about the food, he also refused to pay for it. 这位顾客不仅仅 抱怨食物不好，还拒绝付费。

　　eg. 在任何情况下我都不会相信你。Under no circumstance do I trust you.

　　2、当句首为only加状语的时候，这个句子需要部分倒装。

　　eg. Only with you can I feel happy. eg. 只有当你来了这，我们才可以开始会议。

　　Only when you come, can we start the meeting.

　　3、so......that 结构中的so位于句首时，常引起部分倒装。

　　eg. He runs so fast that I can't catch up with him. 他跑得实在是太快了，以致于我都没有办法追上他。

　　So fast does he run that I can't catch up with him.

　　eg. The moon was so bright that the flowers bright as by day. 皓月当空，花朵就像白天那样的鲜艳。

　　So bright was the moon that the flowers bright as by day.

　　4、句子开头的as 处在第二个单词的位置上，表示虽然的意思。

　　eg. Although I am young, I can live by myself. 虽然我很小但是我却能养活自己了。