了解英语句子中非连续成分的运用无论对于正确理解英语句子的意思，还是用正确汉语来表达英语句子的意思都是至关重要的。
我们都知道，英语大多数陈述句都采用SVO这种线性结构(linear structure)，各成分之间的语法关系是靠语序来体现的，为了准确地表达句子中各成分之间的语法关系，避免歧义，人们在写英语句子时一般要遵循相邻原则(principle of adjacency)，即语法关系密切的两个成分应处于相邻的位置。但是，在实际运用中有时人们并不遵循这一原则，两个应该相邻成分之间被其它成分分隔，构成含非连续成分(discontinuous constituents)的句式。例如：
⑴A wild yell of jubilation to their surprise, went up suddenly from two dozen throats and pandemonium of joy ensued.
--F. S. Fitzgerald: The Diamond as Big as the Ritz
⑵But here on the same road you might have seen among these heavy men a being lithe…
--J. Conrad: Amy Foster
⑶Indeed, if readers find the introduction hard going, they should read just the last section, then plunge into the body of the book, and return to Chapter I when puzzles arise about the general nature of the field.
--S. C. Levinson: Pragmatics
⑷As soon as they were gone, Elisabeth walked out to recover her spirits, or in other words, to dwell, without interpretation on those subjects that deaden then more.
--J. Austen: Pride and Prejudice
上面几个都是含非连续成分的句子，但非连续成分的构成情况各不相同。例⑴句子中的主语A wild yell of jubilation和谓语went up被状语to their surprise分隔，构成主谓非连续成分，例⑵中谓语动词might have seen和宾语a being被状语among these heavy men分隔，构成动宾语非连续成分。例⑶中的中心词puzzles和修饰语被分句的谓语arise分隔，构成名词中心词和后置修饰非连续成分。例⑷不定式动词to dwell和该动词词组的小品词分隔，构成动词副词小品词非连续成分。
在上面四种非连续成分中，最多见的是中心词和后置修饰语非连续成分，这种连续成分比较复杂。除上面例⑶讲的中心词和介词短语修饰语以外，还有以下各种情况。
1、中心词是句子的主语，其修饰语是关系分句，这个关系分句的主语又是关系代词，这种关系分句往往可与中心词分隔。例如：
Some things have been done that ought to have been done long ago.
2、中心词是主语或宾语，同时被两个后置修饰语修饰，其中一个修饰语
把中心词和另一个修饰语分隔。例如：
I've got something important to say.
There is a man downstairs who wants to see you.
The enterprises and property in China of the Japanese aggressors and the chief traitors were confiscated.
Is there anything you want that you have not?
从这几个例句看，造成非连续成分产生的可能是形容词，副词后置修饰语，介词短语后置修饰语,关系分句后置修饰语等。
3、中心词是主语或宾语，状语或插入成分把中心词和修饰语分隔。例如：
There are a lot of people at the bus stop waiting for the bus.
They found a room there to put up for the night.
"Here is the man, " he said, "who told us the good news yesterday."
at the bus stop, there都是状语，he said是插入成分，它们把中心词和修饰语分隔，产生了非连续成分。
4、中心词位于句首，而修饰它的后置修饰语又需置于谓语之后，两者不得不分开。这种情况多见于疑问代词作中心词的句子中。例如：
What did he want to say about it?
Who is there to be criticized?
研究上面所举的所有例句，我们可以发现，英语句子中的非连续成分主要由两个原因造成的，一个是插入语导致产生非连续成分，另一个是为了使句子结构平衡，防止句子产生头重脚轻而产生了非连续成分。
含非连续成分的英语句子的运用，有时与修辞因素有关，即运用非连续成分是为了提高英语句子的修辞表达效果。含非连续成分的英语句子主要有以下几种修辞作用。
1、保持句子结构平稳
由于用文字传递信息的需要，构成句子的各种成分可能会较复杂地交织在一起，这就不可避免地会导致句子结构不平衡的问题，违背句子末端加重(end weight)的原则。例如：
News that the rebels threatened to blow up the city came.
这个句子语法上应该是对的，但修辞效果无从谈起，句子的主语很长，谓语部分只有一个词，太短，句子头重脚轻，失去平衡。现在我们来看下列几例：
When a subject was accused of a crime important enough to interest the king, public notice was given that on an appointed day the fate of the accused person would be decided in the king's arena.
--F. Stockton: The Lady or the Tiger
We watched on TV the two astronauts walking on the moon.
I know of a place on that mountain where we can find this kind of plant.
这几个都是含非连续成分的句子，由于非连续成分的运用，按正常语序的句子所产生的弊端随之消失。句子结构平稳自然，语义严密，修辞效果显而易见。
2、避免句子意思混淆
使用非连续成分有时可以避免句子意思混淆，请看下列例句：
※As I approached the stream I saw a tall man hastening toward me beyond it.
※Once married, the church considers that a couple has signed up for a lifetime contrast.
这两个句子的意思混淆，不合逻辑，原因是beyond it和once married这两个成分在句子中的位置不当。现在我们把它们改成如下形式：
As I approached the stream, I saw a tall man beyond it hastening toward me.
The church considers that a couple, once married, has signed for a lifetime contrast.
这两个都是含非连续成分的句子，第一个句子中宾语和宾语补足语被分隔，第二个句子中分句的主语和谓语被分隔，但两个句子都意思清楚，完全合乎逻辑，非连续成分在某些情况下的优点，在此也可见一斑了。
3、使行文精炼，结构紧凑，言简意赅。
使用非连续成分有时并非为了句子结构平稳，也不是为了避免句子意思混淆，而是为了使行文精炼，句子结构紧凑，语言表达言简意赅。这类非连续成分多数是插入型非连续成分，即插入成分把本来应该相连的两个成分分隔。例如：
I shall propose several sorts of formulations and propose that such sub-collection structures of terms are a resource in the sensitivity to topic of the selection of place formulations.
--E. A. Schlegloff: Notes on a Conversational Practice
从语法上讲in the sensitivity to topic完全可以省略，但句子所含的信息量会随之减少，而这一信息在交际中却是十分必要的。运用非连续成分我们不但不觉得句子罗嗦，而且还觉得行文精确，结构紧凑，言简意赅。再如：
With the establishment during the last century and the flourishing during the present of a modern tradition in American literature, the authority of English opinion and usage has diminished.
--A. Baugh et al: A History of the English Language
显然，在这个句子中，非连续成分的运用与句子结构平衡有否无关，during the last century和during the present的运用主要是为了增加信息量，使信息更有效地传递。它们的运用并不给人冗赘的感觉，而是行文清晰精炼，结构严谨，语义表达确切严密。
不过，使用英语非连续成分切忌弄巧成拙，以免引起不必要的误解。例如：
The only person beside the teacher who knew the matter was the monitor.
在这个句子中，beside the teacher的位置会导致句子的意思产生歧义，因为who knew the matter可理解为修饰person，也可理解为修饰teacher，实际上beside the teacher是状语，应置句首：Beside the teacher the only person who knew the matter was the monitor.再如：
Who is the man reading a newspaper next to the woman?
该句中，next to the woman可理解为man的后置修饰语，也可理解为newspaper的后置修饰语，句子是歧义句，意思含糊不清。应该换一种含非连续成分的句子来表达：Who is the man next to the woman reading a newspaper? 这个句子没有歧义，非连续成分的运用使句子语义表达清楚，这才是非连续成分运用的目的之一。
