为了强调、突出等语的目的而颠倒原有语序的句式叫做倒装句。在倒装句中，颠倒了的成分可以恢复原位而句意基本不变，句法成分不变。
倒装句使用情况：
A. 在疑问句中
各种疑问句一般地说都是倒装语序。例如：
Will they come to see us this weekend ? 这个周末他们将来看我们吗？
Are you talking about the film you saw last Monday ?
你们是在谈论你们上周一看的那部电影吗？
Can you speak another foreign language except English?
除开英语，你还能说另一种外语吗？
Where did you buy the dictionary, in the book store nearby or in Xinhua bookstore?
你在哪儿买的这本词典，是在附近的书店还是在新华书店？
She is not a student, isn't she ? 她不是个学生，对吗？
B. 在感叹句中
某些感叹句也用倒装语序。例如：
Isn't it a beautiful garden ! 多么美丽的花园啊！
What a beautiful garden it is ! 多么美丽的花园啊！
（在这种句式中，主语在谓语之前，属于自然语序。对于主语和谓语而言，语序没有倒装。）
Have you ever seen such a naughty kid like him ! 你见过那个孩子像他这么调皮！
C. 在陈述句中
陈述句在一般情况下用自然语序；但由于英语语法的某些原因，陈述句也要使用倒装语序。这些原因大致可以归纳如下：
1) 为了避免句子部分内容不必要的重复，常用"so + be动词（助动词、情态动词）+主语"或"neither / nor + be动词（助动词、情态动词）+主语"的倒装句式。
其中第一个句式表示"与前面所述的肯定情况相同"， 第二个句式表示"与前面所述的否定情况相同"。例如：
His brother is a college student; so is mine.
他弟弟是大学生，我弟弟也是。
His brother is not a college student; nor is min .
他弟弟不是大学生，我弟弟也不是。
He used to have his further study abroad; so did I.
他曾去国外深造过，我也去过。
He didn't use to have his further study abroad; neither did I.
他没去国外深造过，我也没有。
One of my friends can speak three foreign languages; so can his wife.
我的一个朋友会说三门外国语，他的妻子也会。
One of my friends cannot speak three foreign languages; neither can his wife .
我的一个朋友不会说三门外国语，他的妻子也不会。
They are now preparing for their final examinations; so are we .
他们正在为期末考试作准备，我们也一样。
They are not now preparing for their final examinations; nor are we .
他们没在为期末考试作准备，我们也没有。
2）具有否定意义的词或短语置于句首时（除否定词修饰主语外），句子一般要写成部分倒装句。
这类词或短语常见的有：
not, never, seldom, hardly, rarely, scarcely, by no means, under no circumstances, in no way, at no time, no sooner … (than), hardly … (when), not only … (but also), not until… ,等。例如：
Hardly had she sat down when she heard someone knocking at the door .
她还没来得及坐下来，就听见有人敲门。
Not until twelve o'clock did he go to bed last night .
他昨晚直到十二点钟才睡觉。
Never have my sisters been to Hong Kong before .
我的妹妹们以前从未去过香港。
No sooner had I returned home from New Zealand than I bought a house and went to live there.
我从新西兰一回国，就买了一栋房子并在那儿住下了。
So far as I know, seldom does Mary come back to see her mother.
就我所知，玛利几乎很难回来看她妈妈。
Scarcely a drop of rain fell here last fall . （否定词修饰主语时，句子不用倒装。）
去年秋天，这儿几乎没下一滴雨。
3）当so, often, only等表示程度、频率的副词放在句首时，句子一般要倒装。例如：Only in this way can you come up with a solution to the problem.
只有这样，你才有可能想出解决这个问题的办法。
So serious was the situation that everybody faced a test.
形势如此地严峻，每个人都面临着一场考验。
So hard did he overwork that he fell ill at last. 他太操劳过度以致最后病倒了。
4）当there, here, then, now等副词在句首，且谓语是come, go, be等动词时，句子一般要全部倒装。
其意义在于引起他人的注意。如果这类句子的主语是代词，则不用写成倒装句。例如：
Now, here goes the story.这个故事是这样的。
Look, there comes the taxi.瞧，出租车过来了。
Then came another question.然后又一个问题提出来了。
Then followed the four-year War of Liberation.接下来是四年的解放战争。
5) 当out, in, away, up, bang等表示方位或拟声词放在句首时，句子一般要全部倒装。
这类句子比自然语序的句子更为生动、形象。但如果这类句子的主语是代词，则不用写成倒装句。例如：
Bang goes my ace.我砰地一下打出了"爱司"。
Away flew the bird.那鸟飞走了。
Suddenly, in came a man with a mask on his face.突然进来一个蒙着面具的人。
6) 其他情况还有：省略了if的虚拟条件句、某些表示祝愿的句子、以及某些让步状语从句，等等也要用倒装句式。例如：
（省略了if的虚拟条件句）Had they not helped us, we could not have done it so successfully.
如果没有他们的帮助，我们不可能把那件事办的如此成功。
Should he come, say "Nobody in" to him.
万一他来了,对他说："公司没人。"
（某些表示祝愿的句子）May our friendship last forever.
愿我们的友谊常存！
May your company become prosperous.
祝贵公司生意兴隆！
（某些让步状语从句）Try as I might, I couldn't lift the stone.无论我使多大的劲，我也无法搬起那块石头。
They said they would follow the Party's lead come what might.
他们说无论发生什么情况，他们都会跟党走的。
7) 由于修辞或是平衡句子的原因也可以用倒装句；也可以不用。这不是一条必须的规定。
Next to this one is another grand hotel which is beautifully decorated .
家饭店隔壁还有一家装修华丽的大饭店。
On either side of the great avenue stood many block buildings.
这条大街的两侧都耸立着许多综合楼。（这类句子也可以不用倒装句。）
"I'm leaving for Beijing tomorrow," said Tom to his mother (OR: Tom said to his mother) .
汤姆对他妈妈说："我明天动身去北京。"
Many block buildings stood on either side of the great avenue.
许多综合楼耸立在这条大街的两侧。
Another grand hotel, which is beautifully decorated, is next to this one .
这家饭店隔壁还有一家大饭店，那家饭店装修十分华丽。
完全倒装与部分倒装:
1.完全倒装（Full Inversion）：又称"全部倒装",是指将句子中的谓语全部置于主语之前。此结构通常只用于一般现在时和一般过去时。
谓语+主语+……
①There be（的各种形式）+主语（+地点或时间状语）
例子：
There was a drop in the temperature.温度下降了
There are brids singing in the tree.鸟儿在树上唱歌。
②副词小品词+谓语动词+名词主语+……
③过去分词或现在分词+be的各种形式+主语+……
2.部分倒装（Partial Inversion）（又称半倒装句）：
指将谓语的一部分如助动词或情态动词倒装至主语之前,而谓语动词无变化。
如果句中的谓语没有助动词或情态动词，则需添加助动词do,does或did，并将其置于主语之前。
英语句子的倒装一是由于语法结构的需要而进行的倒装，二是由于修辞的需要而进行的倒装。
前一种情况,倒装是必须的，否则就会出现语法错误；
后一种情况，倒装是选择性的，倒装与否只会产生表达效果上的差异。
倒装的作用:
通常是希望强调句中的某一部分
1. 当以there, here, out , in , up , down, away 等副词开头的句子，为了起到强调的作用，可构成倒装句，只把副词放在句首，主语和谓语位置调换，不加助动词。
Our teacher came in.
In came our teacher.
这种倒装要求：主语必须是名词。主语是人称代词时，主语和谓语语序不变。
Here it is.
Away he went.
这类倒装句式一般只用一般现在时和一般过去时。
Here comes the bus.
Out rushed the boys.
2. how, then, just, often 表示时间的副词放在句首，可构成倒装句，只把副词放在句首，主语和谓语位置调换，不加助动词。
Then came 8 years of the Anti Japanese War.
3. 表地点状语的介词短语放在句首，要用倒装句式，以示强调。
这种倒装句也是主谓直接调换位置，不加助动词did, does或do.
Under a big tree sat a fat man half asleep.
4. there放在句首时，要用倒装句式。
在“there + be”结构中的谓语动词有时不用be , 而用表示类似“存在”观念的其他不及物动词。如：
live, stand, come, lie, flow, enter, rise 和appear等。
There came shouts for help from the river.
There lies a large wheat field in front of the house.
Many years ago there lived an old man in the wooden house.
In front of the tower flews a stream.
5. so + 动词+主语
neither/ nor + 动词+主语
表示两人的同样一个情况时，只能表示一件事，即上、下句所使用的动词、时态要一致。
否则要用so it is with…
You can ride a bike. So can I .
He has been to Beijing. So have I .
The first one isn’t good, neither is the second.
His uncle is a worker and has been working in the factory for more than ten years. So it is with his aunt.
6. so+ 形容词/副词that 的结构状语从句可以用正常语序表示，也可以把so+形容词/副词放于句首构成倒装。
句型如下： so +形容词/副词+be/助动词/情态动词that +从句。
Light travels so fast that it is difficult for us to imagine its speed.
= So fast does light travel that it is difficult for us to imagine its speed.
So easy was the work that they finished it in a few days.
7. done做形容词在句中做表语时，常把表语放在句首，要用倒装句式。
Gone forever are the days when the Chinese people had to use foreign oil.
8. 否定副词not , never, seldom, nowhere, little , rarely 放于句首时要用倒装句式。
We seldom get up at four in the morning.
= Seldom do we get up at four in the morning.
Not a single word from him could the enemy drag.
Rarely have I heard of such a silly thing.
9. hardly…when; scarcely…when…; no sooner…than… 可以用正常语序 had hardly done when… did 或用倒装句式Hardly had + 主语+ done when… did 句式。
hardly所在的句子用过去完成时。
The bell hardly had rung when the class began.= Hardly had the bell rung when the class began.
No sooner had he arrived in Beijing than he began to work.
10. not only… but also 如连接两个成分时，不用倒装；连接句子时，前面的句子要用倒装。
Not only was everything that he had taken away from him, but also his German citizenship.
Not only is he busy, but also I have a lot of work to do.
Not only does he speak English very well, but also he speaks French well.
11. only 及所修饰的副词、介词短语或状语从句放在句首时，要用：
only+ 状语+ be /助动词/情态动词+主语及其他
Only when he told me the news did I know what had happened.
Only in this way can you make progress in your English.
12. 虚拟语气中的倒装句
If I were you, I would take the job. = Were I you, I would take the job.
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