?
A
black hole exerts a strong gravitational pull and it has no matter.黑洞产生
很强的吸引力，可是它没有物质。
? A calorie is defined as the quantity of heat required at one atmosphere to raise the
temperature of one gram of water through 1℃，usually from 14.5℃to 15.5℃.一卡路里定义为在一个大气压力条件下，使一克水温度增加1℃所需要的热量，通常是指从14.5℃ t提高到15.5℃。 ? A chicken is a suitable specimen for the study of the general external features of a
bird.鸡是研究禽类外部特征的合适范例。 ? A collection of data is called a data set, and a single observation a data point.一批
数据叫数据集，（而）单个观测结果叫数据点。 ? A computer is a device which takes in a series of electrical impulses representing information, combines them, sorts them, analyses and compares the information with that stored in the computer.计算机是一种装置，该装置接受一系列含有信息的电脉冲，对这些电脉冲进行合并，整理，分析，并将它们与储存在机内的信息进行比较。 ? A computer work many times more rapidly than nerve cells in the human brain.
计算机工作起来比人类大脑中的神经细胞要快很多倍。 ? A cork floating on water is not swept along with the water. Rather, it moves up
and down with the wave motion.漂在水面上的软木塞没有随波流走。相反，它随波上下浮动。 ? A deep wound, where the supply of blood and oxygen has been cut off, is the
perfect place for certain kinds of bacteria to grow.深的伤口是某些种类的细菌孽生的理想场所，因为那里的供血和供氧被切断。(译为原因状语从句) ? A drilled hole can be made accurate and smooth by a? reamer.钻好的孔可用铰
刀加工，使其尺寸精确，表面光滑。 ? A few people were infected with the AIDS virus through blood transfusions.曾有
少数人通过输血传染上艾滋病毒。 ? A fly wheel stores energy and evens out fluctuations in the speed of the engine.飞
轮可储存能量，因此可使发动机的速度波动平稳下来。 ? A force involves direction as well as magnitude.一个力不仅有大小，而且有方
向。 ? A liquid is made to circulate through pipes in the refrigerator, picking up heat
from the food.是某种液体在冰箱的管子中环流，从而带走食物中的热量。 ? A material object cannot have a speed greater than the speed of light.一个物体的
速度绝不会超过光速。
? A milky white fluid called lymph carries impurities and waste away from the
tissues and passes through gland-like structures spaced throughout the lymphatic system that act as filtering valves.淋巴，一种乳白色的液体，把（人体）各组织内的杂质和代谢废物带走，并通过腺状结构——这些腺状结构分布在所有的淋巴系统内——起着过滤网的作用。 ? A new type of car is now being developed powered by anhydrous ammonia.目前
正在研制一种新型的以无水氨作为动力的汽车。 ? A pilot may have crossed so many time zones, and taken so many irregular breaks,
that he himself does not know when natural night is.飞行员可能越过很多时区，无规律的休息过许多次，因此连他们自己也不知道什么时候是他们的自然夜间。（when 引导宾语从句） ? A polymer is a substance of high molecular weight, well above the size of the compounds considered so far.聚合物是一种高分子的物质，其大小远远超出迄今所提到的各种化合物。 ? A port is a harbor with the necessary terminal facilities to speed up the moving of
cargo and passengers.港口是船只停泊处，有各种必要的终端设备以加速客货流通。 ? A power reactor has no need of air, for the heat generated in the uranium pile is
the result of unclear fission, not of combustion.动力反应堆不需要空气，因为在铀堆中产生的热室核裂变而不是燃烧的结果。 ? A second panel that will visuslly display any alarm condition in the building can
be provided in the Mechanical System Control Office.机械系统控制办公室有另一个仪表板，将清楚地显示楼内的任何险情。 ? A special fund has been set up to help these nations use new chemicals and
technology.已经建立了特殊基金资助这些国家使用新的化学品和新技术。 ? A substance which consists entirely of the same kind of atoms is called an
element.完全由同一种原子构成的物质称为元素。 ? A valuable instrument may be damaged beyond repair in a few second of
carelessness.由于疏忽大意，重要的仪表可在几秒之内被损坏到无法修复的程度。 ? A wave model is considered as a good model of the way in which light behaves.
波动模型是说明光的性能的一个很好的模型。（省译了is considered） ? A wider range of monitor sizes is sought after than ever before.与以前相比，人们追求更大范围的不同的显示器尺寸。 ? About 20 kilometers thick, this giant umbrella is made up of a layer of ozone gas.
地球的这一巨型保护伞由一层臭氧组成，其厚度约为20公里。 ? According to the periodic table, there seem to be still some elements
undiscovered.根据周期表，似乎还有一些未被发现的元素。
? Acid rain, ozone, and other consequences of these pollutants are affecting plant
and animal life.酸雨、臭氧和这些污染引起的其他后果正影响着植物和动物的生存。 ? Administrative personnel should be mathematically informed if they are to make
wise decision.管理人员要做出明智的决策，就应该懂得数学。 ? Adverse to iron, mercury is in a liquid state at ordinary temperature.水银与铁不
同，在常温下是液态。（省译了in） ? Aerodynamics is my field of research.我的研究领域是空气动力学。（主表倒译） ? After all its merits, the alloy does not measure up to the requirements.这种合金尽管有许多优点，但还是不符合要求。 ? After the spring has been closed to its solid height, the compressive force is
removed. 弹簧被压缩到并紧高度之后，就没有压力了。 ? After the war much of this knowledge was poured into the developing of the
computers.战后，这项知识大量地应用于研制计算机。 ? All mater, solid, gaseous or liquid, is made up of extremely tiny particles called
molecules.一切物质，不论是固态，气态还是液态都是由及其微小的叫做分子的粒子所构成的。 ? All of the charges resided on the surface of the conductor.全部电荷都分布在道
题表面。 ? All of the information necessary to build a whole organism resides within a single
cell.成长为整个生物体所需的全部信息都存在于一个细胞内。 ? All that can be done is to convert energy from one form into another.只能把能量
从一种形式转变成另一种形式。 ? All that we know as vitamins, and hormones as well as deadly poisons are all sort
of organic chemicals.我们所熟知的维生素、荷尔蒙以及致命毒药都是有机化学物质。 ? All the sounds are fed into a computer and analyzed.把所有的声音输进计算机
进行分析。 ? All these factors play akey role in formulation of the model.在拟定模型时，所有
这些因素都将起到关键性的作用。 ? Allowance, which is sometimes confused with tolerance, has an altogether
different meaning. “余量”尽管有时和“公差”这个词相混淆，但“余量”这个词却有着完全不同的含义。（非限制性定语从句转译为让步状语从句） ? Although the problem is complicated, an approximation may be obtained by determining the qualitative and quantitative composition of substances.虽然问题比较复杂，单双通过定性、定量地测定物质的成分，则可以近似求解。
? Aluminum is a light, malleable and ductile metal.铝是一种重量轻，可锻造，延
展性好的金属。 ? An engine that converts heat energy into mechanical work is called a heat engine.
把热能转变为机械功的发动机称为热力发动机。 ? An entire disk pack might hold around 300 million bytes or characters.一个整磁
盘可能容纳大约3亿个字节或字符。 ? An increase in final velocity is attainable by means of the multistage rocket.最终
速度的增加可借助多级火箭达到。 ? An increase in the oxygen content of coal by 1 percent reduces the calorific value
by about 1.7 percent.煤的含氧量每增加1%，其热值则下降约1.7%。 ? An insufficient supply of air will prevent complete combustion.空气供应不足将
会妨碍完全燃烧。 ? Any resistor stores some energy in its magnetic field.任何一个电阻器都能够把
一部分能量储存于磁场中。 ? As a result, computer have become smaller, faster, and cheaper.其结果是计算机
变得体积小。速度快，价格便宜。 ? As described above, the laser beam is much more powerful than other light beams.
如上所述，激光束比其他光束要强烈的多。 ? As far as a whole is concerned, the body is electrically neutral, when the total
number of protons equals the total number of electrons.当质子总数等于电子的总数时，这个物体就整体而言是电中性。 ? As far as the image goes, the electron microscope is analogous to the ordinary
optical microscope.电子显微镜就成像而论，与普通光学显微镜相似。 ? As he is a skillful operator , he would work on both the boiler and turbo-generator.
作为熟练的操作人员，他应当能够运行蒸汽炉和涡轮式发电机。 ? As is noted in the preceding section, two essential elements of any computer are a
memory and a processor.正如前一节指出的那样，任何计算机的两个基本单元是储存器和处理器。 ? As is very natural, a body at rest will not move unless it is acted upon by a force.
静止的物体没有外力作用，就不会移动，这是很自然的。 ? As soon as用来引导时间状语从句，可译为“一??就”、“一旦??就”等。
如： ? As the nature of the soil often varies considerably on the same construction site,
the capacity of the soil to support loads also varies.即便在同一施工现场，由于地基的性质有很大差异，土体的承载力也不相同。 ? As the speed of neutrons is reduced, they become thermal neutrons.由于中子减
速，它们变为热中子。
? As we have mentioned above, coal production and use is accompanied by serious
environmental problems.正如我们上面所提到的，煤炭的生产和使用伴随有严重的环境（污染）问题。 ? As引导的比较从句很多情况下不能按以上的固定格式翻译，经常要根据需
要灵活翻译。如： ? At any point in time the slave computer is mirroring the processing of master
computer.从属计算机随时都在反应主计算机的处理过程。 ? At the same time, the infant mortality was 40 percent lower than that of the 1960.
同时，婴儿的死亡率比1960年降低了40%。 ? At this critical temperature, changes begin to take place in the molecular structure
of the metal.在这种临界温度时，金属的分子结构开始发生变化。（译为主语） ? Atomic power stations need very large amounts of water to continually remove unwanted beat.核电站需要大量的水来不断派出废热。 ? Automatic machines,having many advantages,can only do the jobs they have
been told to do.自动化机器虽然有很多优点，但它们只能干人们吩咐它们要干的事。（译为让步状语从句） ? Automation is not the same thing as mechanization.自动化和机械化不是一回事。
?
B
ecause each gene has its unique sequence of difference DNA subunits , the
precise sequence can be registered.因为每个基因的不同的DNA副族都有自己的独特的序列，这一精确的序列可以注册。
? Because of its simplicity, economy, and durability, the induction motor is move
widely used for industrial purposes than any other type of a.c. motor, especially if a high-speed drive is desired.与其他型号的交流电机相比，感应电动机因其简单、经济和耐用而被更广泛地用于工业，特别是需要告诉驱动时更是如此。 ? Before sunshine can be used as a source of energy the storage problem must be
solved.只有解决了贮存问题，阳光才能用作能源。 ? Before the air enters the turbine, fuel is sprayed into it.在空气进入涡轮之前，燃
料就喷进去了。 ? Being cheap and effective makes 2.4-D a very popular weed killer.因为价格便宜
效力高，2.4-D成为深受欢迎的除草剂。（作主语的动名词短语译为原因状语，宾语转译为主语） ? Being ever bulky, the sun does not look larger than the moon from the earth.虽然
太阳体积如此之大，但从地球上看它并不比月球大。