科技
英语长句的从句、短语一般比较长，给
翻译带来了不少麻烦。主要的问题在于这些从句、短语在译文中的位置不好放。如果将它们放在有关词语的前面，会使译文佶屈聱牙，晦涩难懂；放在后面，又感到句子拖沓，结构松散。碰到这种情况，我们不妨采用"括号
翻译法"，即将难以处理的从句（或短与等）译于有关词语后，并加上括号。例如：
This is because power plants, some industrial processes, vehicles and homes emit sulphur and nitrogen compounds, mainly from the burning of fossil fuels, and have greatly increased the amount of them in the environment.
译文一：这是因为，发电厂、某些工业生产过程、车辆和家庭所排放的主要由于燃烧矿物燃料产生的硫化物和氮化物，使环境中这类化合物的含量大大增加。
译文二：这是因为，发电厂、某些工业生产过程、车辆和家庭所排放的；硫化物和氮化物，这些主要是由于燃烧矿物燃料生产的，使环境中这类化合物的含量大大增加。
"译文一"是将作定语的介词短语mainly…fuels译作（前置）定语；"译文二"是将它译于"硫化物和氮化物"的后面。前者定语过于臃肿，不堪卒读；后者结构松散，"这些……产生的"打破了句子的；连贯性。如果我们加括号来翻译，就不会这样了。即：
这是因为，发电厂、某些工业生产过程、车辆和家庭排放硫化物和氮化物（主要是由于燃烧矿物燃料产生的），使环境中这些化合物的含量大大增加。
译文不但结构紧凑，而且一目了然。
在科技英语中，常见的译入括号的句子成分有哪些？本文拟就此问题举例说明如下：
一、定语
1．定语从句
This remains to be established in studies of these chemically modified cotton celluloses in which the amine content is varied over a wide range for each type of composition.这将流待在研究各种化学改性的棉纤维素（每一种的胺含量都有很大变化）时予以确证。
If the soil sample contains an insignificant portion of particals smaller than 0.074mm, as is often the case with cohesion less soils and disintegrated rocks, the hydrometer 0.074 analysis can be omitted.如果土壤样本中小于0。074毫米的颗粒部分微不足道（无内聚力的土壤和松散的岩石通常就是这种情况），就可以进行比重计分析。
2.介词短语
Thus it was possible for us to see how the well-known basic laws controlling all kinds of fluid motion, from ocean currents to water in pipes, had to be adapted to satisfy the ways of the atmosphere. 因此，我们便可能了解那些支配各种流体运动（从大洋的水流到管中的水）的著名定律怎样一定适合于说明大气活动的各种方式。
3.分词短语
Her schedule has brought her almost every honor in running, including eight U.S. records at varying lengths, and a legitimate claim of being the greatest female runner in history.她的成绩表（含八项不同赛程的美国记录）给她带来了跑步方面的几乎的荣誉，从而使她成为有史以来当之无愧的最杰出的女子赛跑运动员。
二、 同位语
译入括号的同位语大多系非限制性同位语。
Gasoline fires should be smothered with sand or with chemicals of some kind, such as those used in some fire extinguishers. 汽油着火应当用沙子或某些化学药品（如某些灭火器中使用的化学药品）来扑灭。
The biosphere, the sphere of life, is probably not so familiar to us as the three physical zones. 我们对生物圈（即生命圈）可能不象对前三个自然带那样熟悉。
有时，除同位语外，尚含其他成分。如：
I remember going to the British Museum one day to read up the treatment for some slight ailment of which I had a touch-hay fever, I fancy it was. 记得有一天我去大英博物馆，专门去查阅我曾患的小毛病（我想是苦草病）的治疗方法。
三、状语
状语从句（可以是条件、让步、方式及时间等状语从句）
On some days the air contains almost, if not quite, as much water vapour as it can hold .有时侯，空气含差不多（如果不是全部的话）它所能容纳的那么多水蒸汽。（也有将这种状语称作插入语的）
Vehicles are usually driven through the agency of the friction between the wheel and the fixed surface, be it rail or road. 车辆通常是通过轮子和固定表面（无论是轨迹还是公路）之间的摩擦作用而行驶的。
And so with the sunshine and the great bursts of leaves growing on the trees, just as things grow in fast movies, I had that familiar conviction that life was beginning over again with the summer. 于是，由于阳光明媚，由于树上的枝叶生长茂盛（犹如快速电影镜头中万物的生长一样），我领悟出那种所习知的信念：随着夏日的来临，生活重又开始了。
As there are 100 of these power surges every second when an A. G. supply with a frequency of 50 e/s used, they are, in fact, too rapid for us to notice. 因为每分钟有100个这种功率波峰（当使用50周/秒频率的交流电源时），所以事实上快得使我们不能觉察。
四、插入语
1．前后有破折号的插入语
Even the simplest operation-the removal of a single joint of a finger, the lancing of an abscess-would prove fatal. 就连最简单的手术（切除一个手指关节，刺破一个脓疮）结果也可能是致命的。
2．前后有逗号的插入语
If the tickets are $2.00 each, you cold make a table, as illustrated in Table I, to compare the number of tickets sold and the amount of money that should be collected. 如果每张票售价两元，你可列一个表（如表I所示），将售出的票数和应当收得的钱数相对照。
但我们要注意的是，过多地运用扩号翻译也不好。不用扩号能译得通顺的，扩号还是不用为好，因为它多少影响到句子的通顺。同时我们应当看到，括号翻译多用于句子的修饰、附加及补充成分，而基本成分（即主语、谓语、宾语和表语等）一般不用扩号。
