第五组；

    （n）either…（n）or…。

    not only……… but also ……

    not ………but ……

    谓语的数与主语的第二部分（即（n）or/ but also/ but引导的后面部分）一致。

    注意比较：

    More students than one have been referred to

    More than one student is going to buy this book

    （四）倒装结构

    倒装是指句子成分不是按主语在前、谓语在后的正常语序排列，而是将谓语或谓语的一部分移到主语之前。倒装是一种修辞手段，目的是为了强调。倒装分为部分倒装和全部倒装，考试多为部分倒装。考生应掌握什么情况下需要倒装，并对倒装后的句子能够认出来，避免做题时候的盲目和迷茫。

    一。 用全部倒装的情况

    全部倒装一般是存在以下列副词开头的句子中，全部倒装的方法是把句子的主谓语序颠倒过来，把谓语移到主语前面：

    1）出于修辞需要，表示方向的副词：out， down， in ，up， away， on.如：

    Down jumped the burglar from the tenth floor when he heard someone shouted at him.

    Up went the plane

    2）出于习惯用法：here， there， now， thus， hence， then.如：

    Now is your turn. There goes the bell.

    Here is a ticket for you

    There existed a certain doubt among the students as to the necessity of work

    注意：here，there用于倒装结构时主语一般为名词，如果是人称代词则不需要倒装

    “ where is the cup？” “Here it is！”

    Here you are.

    There he comes.

    3）有时主语较长，为了使句子平衡，避免头重脚轻，主谓要全部倒装。这种情况多出现在主系表结构中。如：

    Less important than ever is developing a meaningful philosophy of life.

    In between these two extremes are those people who agree with the jury system as a whole， but feel that some changes need to be implemented to improve its effectiveness.

    二。 采用部分倒装情况

    部分倒装一般是把句子谓语的一部分（主要是助动词或系动词）放到句子主语前，构成部分倒装，而全部倒装则把句子的谓语（包括实义动词）都放在主语前

    1.下列否定词及含有否定意义的词组修饰状语时，若置于句首，句子的主谓要部分倒装，：

    never， no， neither， not only， hardly， scarcely， little， seldom， rarely， not until， nowhere， at no time， on no account， in no respect， in no sense， by no means， in vain， still less.如：

    Not only is its direct attack on their discipline， it bypasses the essence of what sociologists focus on.

    Under no circumstances should we do anything that will benefit ourselves but harm the interests of the state.

    （1985年考研题）

    注：1）如果谓语动词是单个实义动词，倒装时需根据人称和时态加助动词do.如：

    Little did we expect that he would fulfill his task so rapidly.

    （1983年考研题）

    2）考生要广义理解“句首”的概念，注意从句的句首和并列分句的句首均为句首。如：

    Suddenly， Gallup's name was on everyone's lips； not only was he the prophet of the moment， but it was generally believed that he had founded a new and most important method of prediction.

    2.以only修饰状语（副词，介词短语，状语从句）开头的句子，句子的主谓要部分倒装：

    only then， only at that time， only once， only in this way， only with， only through， only by， only when， only after， only because.如：

    Only when you have obtained sufficient data       come to a sound conclusion.