75.You will remember that the materials which combine to make a mixture do not completely lose their individual qualities．They do not do so because their molecules are not broken up and built into new molecules with new qualities．

　　你们要记住，组成混合物的各种物质完全没有失去它们各自的性质。它们之所以这样，是因为它们的分子并没有分解，没有形成具有新性质的新分子。(不定式短语to make a mixture是谓语combine的结果状语。)

　

76．The moon's pull causes water in the oceans to be a little deeper at the point closest to the　moon and also at a point farthest from themoon，on the oppositeside of the earth．

　　月球的引力会引起近月点处和地球另一端的远月点处海洋的海水略深一些。(cause sth．To do sb，“引起……作……”。to be alittle deeper．．．作water宾语补足语。)

　

77．　It is also a familiar fact that a force is required to slow down or stop a body which is already in motion，and that a sidewise force must be exerted on a moving body to deviate it from a straight line．

　　要使一个已经运动的物体慢下来或使其停止运动就需要作用力；要使该物体偏离直线运动，就需要横向作用力，这也是大家所熟悉的事实。(it是形式主语，代替that引出的两个主语从句。不定式短语to deviate．．．1ine是目的状语，其中it代替the moving body。)

　

78．Though only l07 elements have been discovered，they combine in enough different ways to make the millions and millions of different things in the world．

　　虽然只发现了107种元素，但是这些元素以不同的方式化合在一起就会形成世界上无数的千差万别的东西。(不定式短语to make．．．作结果状语，说明enough。)

　　

79．Since we have already associated flow of charge or current with the existence of potential difference，it becomes of interest and importance to establish a quantitative relation between these two quantities．

　　因为我们已经把电荷的流动即电流与电位差的存在联系起来，因而在这两个量之间确立一种数量关系就成为重要而值得注意的问题了。(不定式短语to establish．一quantities是主语，it是形式主语。)



　 80．Apart from the enormous outflow of funds from the oil-consuming countries，a more basic　concern is the capability of the major exporters of crude oil to achieve a continuing production target　roughly doubling output every tenyears to meet the required oil demand if present trend continues．

　　且不谈用油国的资金大量外流，更令人担心的重要问题是：如果目前的这种趋势继续发展下去，那么主要原油出口国是否有能力每10年大致将产量翻一番以满足对石油的需求。

(a-partfrom，“除了，且不说”。of．．．oil作capability的定语，不定式短语to achieve．．．continue也作定语，修饰capability。这个不定式短语中包含有：现在分词短语roughly doubling．．．continue。这个短语中又包含有不定式短语作目的状语to meet．．．continue和if引导的条件状语，这两个状语都用来修饰doubling。)

81．Television makes it possible for us to see a distant scene as a transmitter at the television　stadio telecasts the scene to our receiver．

　　当电视台的发射机把场景播送到我们的接收机时，电视就使我们能看到远处的场景。(it，是形式宾语，真正的宾语是for us to see a distant scene。)



　 82．This failure of an object to regain its original size and shape as soon as the deforming force　is removed is called elastic lag．　　

　　一旦形变力除去之后，物体不能恢复原来的大小和形状，这种现象称为弹性滞后。(fail-ure是名词，在句中作主语。不定式短语to regain．．．shape作failure定语。)



　 83．The purpose of this book is to introduce to the students solutions of problems having close　connection with application in industry．

　　本书的目的是向学生介绍一些习题的解法，这些习题与工业中的应用有着密切的关系。

　(不定式短语to introduce．．．industry是系词is的表语，用来揭示purpose的内容。)



　　84．It is clear that insulating materials should have such a high specific resistance as to be，to all intents and purposes，nonconductors of electricity．

　　显然，绝缘材料具有很高的电阻率，因而实际上是不导电的。　(that引出主语从句，it是形式主语。such．．．as to be non-conductor．．．表示结果。to all intents and purposes，“实际上”，“事实上”。)



　 85．The most probable explanation of radioactive disintegration is to be found in terms of the modern ideas concerning the structure of matter．

　　必须根据物质结构的现代观点才能更好地阐明放射性裂变现象。(is to be found是复合谓语结构，有“应该”，“必须”的含义。in terms of，“根据”。concerning．．．是介词短语，修饰ideas。)

86．In solids the molecules are relatively close to each other and the forces of attraction are great enough to hold the molecules in a regular pattern and thus maintain a definite volume and　shape.

在固体中，分子彼此结合得很紧密，分子引力大得足以使分子保持在有规则的结构中，从而使固体能维持一定的体积和形状。　(to hold．．．and．．．maintain．．．是不定式短语，起结果状语作用，说明enough。)

　

87．it is impossible for a sdf-acting machine，unaided by any external agency，to convey heat　from one body to another at a higher temperature．

　　不借助于任何外在因素，自动机不可能把热能从一个物体传递给另一个温度较高的物体。

(不定式短语to convey．．．temperature在句中作主语，it是形式主语，for．．．machine是不定式toconvey的逻辑主体。分词短语unaided．．．agency起状语作用，有条件的意味。)



　 88．The sun can be said to be the source of nearly all energy，　and in the absence of the sun’sheat and light, no life could exis to nearth．

　　可以说太阳是几乎所有能量的来源，因此，如果没有太阳的光和热，地球上就不可能有生命。(tobethe．．．energy作sun的补足语。)　　

　

　89。To appreciate the capabilities and limitations of radar，and so to be able to use it to full ad—vantage，it is necessary to understand the character and behaviour of radio waves and to appreciate the principles of their generation and reception，including the presentation of echo to the observer为了正确了解雷达的能力和局限性以便能充分地利用它，就有必要了解无线电波的特性和作用，而且要了解它的产生和接收的一些原理，包括对观察者所产生的回波。　(Toappreci-ate．．．radar和so to be able．．．advantage都是目的状语。to understand．．．waves和to appreciate．．．observer都是主语，it为形式主语，代替这两个不定式短语。现在分词短语including为伴随状语，用来对上句谓语表示的行为进行补充说明。to full advantage，“充分地”。)

90．　Pollution and waste combine to be a problem everyone can help to solve by cutting out un-nessary buying，excess consumption and careless disposal of the products we use in our daily lives．

　　这些污染物和废物结合在一起就会造成一大问题。每个人可以帮助解决这一问题：不去购买不必要的东西、削减过量的消费、不要粗枝大叶地处置日常生活中所使用的物品。(这是一个主从复合句。主句Pollution．．．problem。everyone．...daily lives是省略that的定语从句，修饰 problem，that在定语从句中作宾语时，可以省略。句中Pollution和waste是主语，谓语是combine，不定式短语to be aproblem为结果状语。we．．．use。．．1ives也是省略that的定语从句，修饰products。)

　

　91．Chemicals are made from the elements which have been put together in different forms to make wood or glass or rugs or water，or even the bones，blood，and muscles of ourbodies．

化合物是由那些不同形式组合在一起而构成了木头、玻璃、毯子、水或者甚至我们身体的骨骼、血液和肌肉的元素组成的。(不定式短语to make．．．是结果状语，说明谓语have been put。)



　 92．We notice that every day the sun appears to travel across the sky from east to west，but many people have not noticed that the stars also move across the sky in the same direction．

　　我们注意到，太阳每天看来是从东到西越过天空，但是很多人没有留意到星星也是沿着同样的方向越过天空的。(不定式短语to travel．．．是系词appears的表语。)



93．The invention of the thermometer，the barometer，and the hydromter in the sixteenth and seventeenth centuries extended man’s capability to observe，and sharpened his desire to interpret and to understand．

　在16世纪和17世纪发明了温度计、气压计和比重计，这就扩大了人的观察能力，并加强了人们解释和认知(自然界)的愿望。　(to observe修饰capability。to interpret and to understand修饰desire。)



94．Intelligent beings which are just beginning to develop on remote worlds may be ready to pick up our signals in thousands of years’time，or when life on earth has become extinct．

　在遥远的星球上现在刚开始进化的有智慧的生物，也许要在千万年以后，即在地球上生物绝迹后，才能收到我们发出的信号。(ready是形容词，不定式短语to pick up．．．作其状语。)

　

95．When the effect of inductance is such as to cause an induced voltage in the salne circuit in which the changing current is flowing，the term self-induction is applied to the phenomenon．

　当电感效应在变化的电流流过的同一电路里足以引起感应电压时，我们就用“自感”这个词来描述这一现象。(such as引导的不定式短语to cause．．．表示结果。)

96．It was not until the 19th century，when magnetism was shown to be the product of electricity，that serious research into the nature of permanent magnetism began．

　直到19世纪证明了磁是电产生的那个时候，人们才开始对永久磁性的本质作认真的研究。(to be the product．．．为主语补足语，说明magnetism。)



　97．A rocket is independent of air because it contains an explosive mixture which consists both of a fuel to beburned and a supply of oxygen．

　火箭飞行依赖空气，因为它本身装有爆炸混合物，这种混合物是由待燃烧的燃料和氧气组成的。(to be burned在句中作定语修饰fuel，有“将来”的含义。)



　　98．The first law of motion explains what is to be understood by force: it iS that which tends to change the state of rest of aboby，or of uniform motion in astraight line．

　第一运动定律阐明了对力应该怎样理解：力就是改变物体的静止状态或匀速直线运动状态的作用。(“be+不定式’’有情态动词的意思，即“可能”，“应该”，“必须”。)　　



99．In almost every cause the electric current that an ammeter measures must actually pass through theinstrument，so thismetermust beconnected inserieswith the circuit inwhich it is to measure the current．

　　几乎在所有的情况下，安培计所测量的电流实际上必然要通过该电表，因此安培计必须与待测电流的电路串联在一起。(句中“be十不定式”有表示“将要”的意思。)