倒装有两种情况：
部分倒装（主语和助动词倒置）和全部倒装（主语和谓语完全倒置）.之所以使用倒装,一是为了句子的需要；二是为了语法结构的需要.?
一、为了句子意义的需要
也就是为了强调句子的某一内容,并使上下文衔接紧密；或为了保持句子平衡.常见有下列情况：?
1.句子谓语是go,come,run等表示位置的动词和be动词,句中又有表示方位的副词（如the re,here,up,down,out,in,away等）,为了强调该副词,可将其放于句首,而将谓语动词全部置于主语之前.如：?
Here comes the train to Beijing. 去北京的火车来了.?
There goes the bell. 铃响了.?
Down came the rain. 下雨了.?
但主语是人称代词时,主语仍置于动词之前.如：?
Away he comes. 他来了.?
Here it comes. 它来了.?
2.为了强调句中的状语或表语,为了保持句子平衡或上下文衔接紧密,可将状语或表语置于句首,句中主语和谓语完全倒装.如：?
At the front of the hall sat the headmaster.?
校长坐在大厅的前部.?
In this paragraph can be found an answer.?
在这段里能找到答案.?
3.为了强调only及其所修饰的状语（通常是副词、介词短语或从句）,则将它们移到句首,句中的主谓作部分倒装.如：?
Only then did we realize that the man was blind.?
直到那时我们才发现那个人是盲人.?
Only when the war was over in 1918 was he able to get happily back to work.
直到1918年战争结束后,他才得以愉快地重返工作岗位.?
4.将含有否定意义的副词（never,seldom,not,little,hardly等）置于句首以示强调时,句中的主谓作部分倒装.如：?
Seldom in my life have I met so determined a person.
一生中我很少见到如此果断的人.?
5.为了强调“not a+名词”或“not a single+名词”结构,将其置于句首时,句中的主谓作部分倒装.如：?
Not a word did he say at the last meeting.?
在上次会议上他一句话都没说.
6. Hardly…when,no sooner…than,not only…but also引导两个分句时,将前一个分句中的主谓作部分倒装,后一个分句中的主谓语序不变.
如：?
Hardly had he began to speak when his father stopped him.
他刚开口发言就被父亲制止了.?
No sooner had I left my house than it began to rain.?
我刚刚离开家就下雨了.?
但neither/not…nor引导两个分句时,这两个分句中的主谓均要倒装.如：?
Neither do I know her address,nor does he.?
我不知道她的地址,他也不知道.?
Not could the patient eat,nor could he drink.?
那个病人既不能吃,也不能喝.?
7.在“so+形容词…that分句”结构中,如将“so+形容词”置于句首以示强调时,其后的系动词be则要移到主语前面,形成主谓的完全倒装.如：?
So moved was she that she could not say a word.?
她激动得一句话也说不出来.?
在“so+副词…that分句”结构中,如将“so+副词”置于句首以示强调时,其后的主谓作部分倒装.如：?
So loudly did he speak that even the people in the next room could hear him.
他的声音那么大,连隔壁屋子里的人都听得见.?
So fast does light travel that it is difficult for us to imagine its speed.
光速如此之快,我们很难想象.?
二、由于语法结构的需要使用倒装.常见于下列句型：?
1.“So+助动词+主语”是一种常用于对前面所说的情况作简短回答的句型.如：?
I was late and so was she.?
我迟到了,她也迟到了.?
They love having lots of friends,so do those with disabilities.
他们喜欢广交朋友,残疾人也一样.?
2.“Neither/Nor+助动词+主语”是用于对前面所说的否定内容表示同样看法的句型.如：?
She won”t go. Neither/Nor will I.?
她不走,我也不.?
I cannot swim. Neither can he （swim）.?
我不会游泳,他也不会.?
3.当if引导的虚拟条件从句中含有had,were或should等时,如将if省略,则要将had,were或should等移到主语前,作部分或完全倒装.?
Had you come yesterday,you would have seen him.
若你昨天来,你就会见到他了.?
4.表示存在的句型“There be+主语”也属于倒装句之列.如：?
There are three chairs,a desk and a computer in the room.