因果关系的描写在英语科技写作中常常用于以下几方面：（1）进行逻辑论证；（2）解释某事为什么以某种方式发生；（3）对未来的事件进行预测；（4）解释一个过程。

逻辑关系清晰是因果分析的关键之处，但在实际写作中这一点却往往不容易做到。因为一个原因可能有多种结果，而一个结果也可能是由多种原因造成的；而且在写作中，我们并非总是按照因果顺序来分析逻辑关系的；对因果关系的描述也并非总是肯定的，有时也会用到推测、怀疑、甚至否定的描写。因此，为了有效地表达出不同的因果关系，我们必须学会运用不同的写作技巧。

1.由因到果

由因到果是因果分析中最常见的一种方法，它可分为两种：一因导致一果，一因导致多果。常见的表达有：

This accounts for the fact that...

It was partly for these reasons that...

Because（As/If/Since/Now that/Seeing that）...

Because of（On account of/Owing to/Due to）...

This explains why.../Tha$'why.../for this reason

As a consequence/As a result.../The consequence is...

In view of the fact that/On account of the fact that/Owing to the fact that...

...，so/therefore/thus/hence/consequently...

...cause（generate/yield/bring about/give rise to/result in/lead to/etc.）...

以下两段描述的是一因一果的关系：

例1：

People are said to compare themselves with others on the basis of a complex set of cues，many of which are partially heritable.The consequence is that spouses are genetically more similar to each other than they are to the average person.

例2：

Combustion catalysts consist of various shapes of basic material coated with a metallic compound.The variety of shapes and catalytic materials provides a multitude of catalysts for each application.Therefore，a good general rule to follow is to consult with a catalyst manufacturer on the most suitable catalytic equipment configuration.

一因多果的描写比一因一果要复杂一些，请看下段：

例3：

If，however，children grow up without love and without feelings of selfworth，they feel unlovable and worthless and expect to be cheated，taken advantage of，and looked down upon by others.Ultimately their actions invite this treatment，and their self-defeating behavior turns expectations into reality.They do not have the personal resources to handle everyday problems in a healthy way，and life may be viewed as just one crisis after another.Without a healthy self-esteem they may cope by acting out problems rather than talking them out or by withdrawing and remaining indifferent toward themselves and others.These individuals grow up to live isolated，lonely lives，lacking the ability to give the love that they have never received.

一因多果有可能是一个原因导致几个平行的结果，如在该段中，“children grow up without love and without feelings of self-worth”导致了以下结果：

A.They expect to be cheated，taken advantage of，and...

B.They do not have the personal resources to handle everyday problems...

C.They may cope by acting out problems rather than...

D.These individuals grow up to live isolated...

在该段中，我们可以看出，作者运用“If，they，They，Without，they，These individuals”等几个“traffic signals”使因果关系层次分明，几个平行的结果一目了然。

一因多果还可能是一个原因导致一个结果，而这个结果又成为另外一个结果的原因，即连环因果关系。如本段的一二句就是一个连环因果关系：If children grow up without love and without feelings of self-worth→they feel unlovable and worthless and expect to be cheated，taken advantage of，and looked down upon by others→their actions invite this treatment，and their self-defeating behavior turns expectations into reality。

描述连环因果关系，最重要的就是要充分利用英语的“连接”手段使各对因果关系层层嵌套、紧密联系。请看例4和例5。

例4：

If a supernova（the explosion of a massive star）triggered star formation from dense clouds of gas and dust，and if the most massive star to be formed from the cloud evolved into a supernova and so on，then a chain of star-forming regions would result.If many such chains were created in a differentially rotating galaxy，the distribution of stars would resemble the observed distribution in a spiral galaxy.

例5：

One of the most important properties of a liquid is that its surface behaves like an elastic covering that is continually trying to decrease its area.A result of this tendency for the surface to contract is the formation of liquids into droplets as spherical as possible considering the constraint of the everpresent gravity force.Surface tension arises because the elastic attractive forces between molecules inside a liquid are symmetrical；molecules situated near the surface are attracted from the inside but not the outside.The surface molecules experience a net inward force；and consequently，moving a surface molecule out of the surface requires energy.

2.由果到因

在描述因果关系中，“由果到因”也是常用的一种分析方法，它可以分为两种：一个结果追溯一个原因，一个结果追溯多个原因。

（1）一个结果追溯一个原因：

...result from...

...because/since...

...is attributable to（due to/effected by/etc.）...

...is determined by（decided by/caused by）

As a result of...

This is because...

The reason for...is...

The reason why...was that...

例1：

We do have reasons to believe that there may have been more than one genetic line among the eleven wasps at the time of the fission.This is because several females had simultaneously been laying eggs in this colony in the past.

例2：

A one-million-fold increase in speed characterizes the development of machine computation over the past thirty years.The increase results from improvements in computer hardware.

（2）一个结果追溯多个原因

...is essential for..reasons

...for a number of reasons

...could be attributed to...，to...，or to...(www.daowen.com)

...could be achieved because of...and...

...is found to be...because of the following reasons...

...may probably be attributed to the fact that....In addition，...may be caused when...

Because...，and because（of）...

Be associated with...，...and...

In addition to considering...，...are included.

例3：

We recommend the purchase of the New Orleans heat exchanger because

① it can be obtained for$25，000，a savings of 80%over the new cost，

② production could be increased by 28%if needed，8%higher than requested，

③ it will help recoup losses incurred in our benzene plant.

例4：

Comparative data which analyze marriages of different lengths are subject to the qualification that any change identified could be attributed to convergence（or divergence if correlations decrease），to changing patterns of mate choice or to a selective process.

3.推测因果关系

当我们推测某事发生的原因或预测未来可能发生的事件时，常常要用推测的语气来描述因果关系。

常用的表达有：

...imply...

...may result in...

...may be influenced by...

...might be explained by...

...have been implicated as...

...would support the view that...

If...，...would...

It is possible that...

This may be due to...

It seems likely that...

Possibly this is part of the reason that...

It is suggestive that.../It suggests that...

These are assumed to have an effect on...

例1：

The first theories of such grazer control were merely based on observations of negative correlations between algal and zooplankton numbers.A low number of algal cells in the presence of a high number of grazers suggested，but did not prove，that the grazers had removed most of the algae.

例2：

In the main Hawaii study it may be seen that correlations for education level were higher than those for general or specific IQ factors，so it seems likely that the latter might be entirely explained by the former.

4.怀疑或否定因果关系

科学需要怀疑精神，许多伟大的思想和发明都是在怀疑和否定已被公认的“定理”中诞生的。因此在科技写作中，必不可少地要用到怀疑或否定因果关系的描写。

常用的表达有：

...can/do not prove...

...appeared to be unrelated to...

...can advance not a single reason for...

...would have difficulty accounting for...

...does not provide a satisfactory explanation for...

...cannot be the only or the principal factor accounting for...

It is not clear whether...are...

Although...do not account for...

However，they do not take into account...

From...'s viewpoint there is no reason to...

It will be seen that...'s reasons for...are rather precarious ones.

例1：

It can be unpleasant to live even several miles from an aerodrome；if you think what it must be like to share the deck of a ship with several squadrons.But neither psychiatric interviews nor objective tests were able to show any effects upon these American sailors.This result merely confirms earlier American and British studies:if there is any effect of noise upon mental health it must be so small that present methods of psychiatric diagnosis cannot find it.That does not prove that it does not exist；but it does mean that noise is less dangerous than，say，being brought up in an orphanage—which really is a mental health hazard.

例2：

The conclusion that emerges from these studies is that although there is considerable assortative mating for education level and a strong relationship between education and intelligence，education level and other background variables do not account for all the assortative mating for intelligence.