倒装(inversion)是一种语法手段，用以表示一定句子结构的需要和强调某一句子成分的需要。英语的最基本的结构是主、谓结构，倒装就是将这种比较固定的词序加以颠倒。
倒装有两种。将主语和谓语完全颠倒过来，叫做完全倒装(complete inversion)。如Then began a bitter war between the two countries。于是两国之间开始了恶战。
只将助动词(包括情态动词)移至主语之前，叫做部分倒装(partial inversion)。如At no time was the entrance left unguarded。入口无时无人把守。
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。
例1Among the advantages that future biochips, or “living computers”， would have over conventional semiconductor chips are that they are smaller, they do not generate as much heat, and they allow for the parallel processing of information, making them faster than today’s semiconductor devices。
例2This is the world out of which grows the hope, for the first time in history, of a society where there will be freedom from want and freedom from fear。
注意：调整语序，加强语气。
以There be引出的倒装句
a. There seem to be many good candidates in the district。
b. There exist many problems among the present day students。
c. There appears to be a man in black in the distance。
以副词here, there, then, now, next引出的倒装句
a. Here come the rest of the party。
b. Now comes your turn。
c. Then followed the discovery of a new compound。
d. Next came Edward with his wife。
以表地点的介词短语引出的倒装句
a. At the school gate stood a guard。
b. Under the tree are sitting some students。
c. On the bed lay a pretty kitten。
主语为代词时，不用倒装
Behind the counter he stood。
Behind the counter stood a man with glasses。
以表方位的副词引出的倒装句
a. Up went the arrow into the air。
b. Down fell a dozen apples。
c. Off went the horse。
not短语置于句首
a. Not until he went abroad did he know the truth of the fact。
b. Not a moment did she waste on campus。
c. Not only did I know her, but I was her best friend。
d. Not simple is this book interesting, but also instructive。
no短语置于句首
a. By no means should he be left alone。
b. In no way are can we allow this to continue。
c. In no case are you to leave your post。
d. On no account should we follow blindly。
e. Under no circumstances can we create or destroy energy。
f. No longer are they staying with us。
g. No sooner had she finished the poem than the students began go ask her questions。
only置于句首
a. Only by this means is it possible to explain his failure to act decisively。
b. Only after making investigation can we have the right to speak。
c. Only when one loses freedom does one know its value。
比较状语从句中的倒装
a. He ran as fast as did the person who came from England。
b. I spend less than do nine out of ten people in my position。
c. The greater the number of the free electrons in a material, the better is the conductivity of the material。
让步状语从句中的倒装
a. Small as atoms, electrons are still smaller。
b. Complex as it may appear, the rocket, which was invented in China over 800 years ago, is a relatively simple device。
c. Hard as I tried to explain it to him, he still didn’t understand。
d. Much as I disagree with you, I yet respect you。
e. Vague though its category (is)， it is without doubt an essay。
f. Try as he would, he could not lift the rock。