当主语在谓语前出现时叫顺序（the natural order）。在某些情况下，我们可以把谓语成分放在主语前面，这种词序叫做倒装（the inverted order）。
倒装分两种：配合语法条例的倒装，叫“grammatical inversion”；配合强调语势的叫“emphatic inversion”。
语法上的倒装句是强制性的，包括下列7种：
1、疑问句，如：
Can you do it?
How old are you?
When did you know him?
Why did you elect him as captain?
Which of these apples do you prefer?
但疑问代词做主语时，不必倒置，如：
Who is your English teacher?
What happened last night?
2、表示“愿望”的句子，如：
May God bless you.
Long live the king!
3、“There”引导的句子，如：
There are many cars on the road.
There stand some big trees near the river.
There is a security guard outside the bank.
4、感叹句，如：
How beautiful the flower is!
What a smart boy you are!
5、有连接词“so,neither,nor”的句子，如：
Tom can ride a bicycle;so can I.
She can't sing;neither can he.
John has never been late;nor have I.
6、省略连词“if”的条件副词分句，如：
Were I you,I would not do such a thing.
Should the machine break down again,send it back to us.
Had you worked harder,you would have passed.
7、“as,however”连接的让步副词分句，如：
Small as the pen is,it is a powerful weapon.
However busy you are,you should spend some time reading Zaobao weekly.
谈过了语法上的倒装句，现在谈强调的倒装句。
Never have I seen such a wicked man.
On no account must this employee be removed.
Not until he told me had I heard anything of it.
No sooner had I left than the rain came.
Up jumped the puppy.
In came John.
Down fell the rotten branches from the tree.
Out came a woman and her maid.