倒装      

   谓语动词放在主语之前的这种语法现象称为倒装。从倒装的形式来看，可分为全部倒装(full inversion)和部分倒装(partial inversion)两种。前者是指整个谓语置于主语之前，而后者仅是指助动词、情态动词或be 动词等功能置于主语这前。

    引起倒装的情况多种多样，倒装的表现形式大体有下列几种：

    1．在疑问句中

    例1：How are you getting along with your work?

    例2：Is this report written in detail?

    注：如疑问词作主语或者作定语修饰主语时，不发生倒装。

    2．在there be 及其类似结构中

    例1：There are forty students in our class.

例2：There seem to be still some elements undiscovered yet.

    例3：There stands a bridge across the river.

    3．在表示祝愿的句子中

    例1：Long live the People’s Republic of China!

    例2：May you succeed!

    例3：Dog-tired though they were, they continued to march on.

    4．在省略if 的虚拟语气条件状语从句中

    这类句子中有were, had, should等词时，把were, had或should置于句首。

    例1：Were there no air or water, there would be no life in the world.

    例2：Had you been more careful, such spelling mistakes might have been avoided. （对过去的虚拟

    5．在so, nor, neither或no more开头的句子中

    此类句子通常表示前面一句话中的谓语所说明的情况，也适用于另一句中的主语。例如：

1）This problem is not difficult and neither is that one.

    2）Coal is under the ground in some places, and so is oil.

    6．在以具有否定意义的副词、连词及词组开头的句子中

    这些词和词组通常有：rarely, never, scarcely（几乎不，简直没有）, no sooner, little, few, hardly, seldom, at no time, in no way, on no account, nowhere, nobody, not only等。

No sooner…than   刚。。。。就。。

这是一个连词，sooner是soon的比较级形式，只能与than连用，而rarely，scarcely，barely,hardly则需要与when连用。他们都表示“刚。。。就。。。”的意思，前半句多用过去完成时

如，we had no sooner reached the station than the train was off.

 The performance had scarcely begun when the light went out.

当no sooner，hardly，scarcely，barely放在句首时，在than以前的那部分句子需要用倒装语序。

如，hardly had he gone to bed when he heard a knock at the door.

 No sooner had we reached the conclusion than they agreed to it.

（agree on/upon =agree about/in    agree to +建议或安排