英语中 什么时候句子需要倒装?

英语的基本句型是主语 + 谓语.如果将主语与谓语调换,称倒装句.
装句分全倒装句和半倒装句.
一、 全倒装:主语与谓语交换位置不需任何助动词,叫全倒装.全倒装有以下三种情况:
1、当here,there,out,in,up,down等副词放在句首时,句子需全倒装:
There goes the bell!铃响了!There lived an old man.Here comes the bus.注意:①在这种情况下倒装仅限于不及物动词或be动词,像go,come,mush等.②主语如果是代词时不需倒装如Away he went.他走远了.
2、方位状语在句首,如:
In front of the house stopped a police car.
Nearby were two canoes in which they had come to the island.
Under the tree sat a boy.
3 、直接引语在句首,这种情况可倒装也可不倒装
"What does it mean?" asked the boy或the boy asked.
二、半倒装:主语与谓语的助动词交换位置称半倒装,有以下数种情况:
1,否定意义的词在句首,句子半倒装,例如:little,never,not,no,hardly,rarely,seldom
Never shall I forget you.At no time was the man aware of what was happening.
Little did I understand what he said to me at that time.
2、 几对并列连词如not only…but also,hardly… when等连接两个并列句,连词在句首,前句半倒装,后句不倒装:
Not only was everything he had taker away from him,but also his German citizenship was taken away.
No sooner had I got to the bus stop than the bus started.
注意:①not only…but also连接两个并列主语时不需倒装,如:Not only you but also I like playing chess.
②neither…nor在句首时,前后两句都需倒装,Neither do I have a sister nor does my husband.
3、only在句首强调状语,主句半倒装:
Only then did I realize that I was wrong.Only in this way can I learn from my fault.
Only when the war was over in 1918,was he able to get back to work.
注意:only强调主语不倒装:Only the teachers can use the room.
4、so…that句型,so在句首时,主句倒装,that从句不倒装:
So easy is it that a clild can learn it.So hard did he work that he finally won the fame.
I saw the film,so did he.
5.省略了if的虚拟条件句
Had I been informed earlier,I could have done something.Were she here,she would support the motion.