1. 否定副词位于句首时的倒装

在正式文体中，never, seldom, rarely, little, hardly, scarcely, no sooner, no longer, nowhere 等含有否定意义的副词若位于句首，则其后要用部分倒装：

I shall never forgive him. / Never shall I forgive him. 我永远不会宽恕他。

He seldom goes out for dinner. / Seldom does he go out for dinner. 他很少出去吃饭。

She hardly has time to listen to music. / Hardly does she have time to listen to music. 她几乎没时间听音乐。

He little realizes how important this meeting is. / Little does he realize how important this meeting is.

他不甚明白这个会议的重要性。

We had no sooner reached the airport than the plane took off. / No sooner had we reached the airport than the plane took off. 我们刚到机场,飞机就起飞了。

【注意】

(1) 对于not…until句型，当not until…位于句首时，其后的主句要用倒装语序：

He didn’t leave the room until the rain stopped. / Not until the rain stopped did he leave the room. 雨停了之后他才离开这房间。

(2) 某些起副词作用的介词短语，由于含有否定词，若位于句首，其后要用部分倒装：

On no accounts must this switch be touched. 这个开关是绝不能触摸的。

In [Under] no circumstances will I lend money to him.无论如何我也不会再借钱给他了。

但是，in no time(立即，马上)位于句首时，其后无需用倒装语序：

In no time he worked out the problem. 他马上就算出了那道题。

2.“only+状语”位于句首时的倒装

当一个状语受副词only的修饰且置于句首时，其后用部分倒装语序：

Only then did he realize that he was wrong. 到那时他才意识到他错了。

Only in this way are you able to do it well. 你只有用这种方法才能把它做好。

Only when he returned home did he realize what had happened.

当他回到家里时，才知道出了什么事。

3. “so+adj. / adv.”位于句首时的倒装

副词so后接形容词或副词位于句首时，其后用部分倒装：

So cold was the weather that we had to stay at home. 天气太冷，我们只好呆在家里。

So fast does light travel that we can hardly imagine its speed.

光速很快，我们几乎没法想像它的速度。

So sudden was the attack that we had no time to escape.

袭击来得非常突然，我们来不及逃跑。