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  3. You should spend about 20 minutes on Questions 27-40 which are based on Reading

You should spend about 20 minutes on Questions 27-40 which are based on Reading

游客2025-02-15  1
问题 You should spend about 20 minutes on Questions 27-40 which are based on Reading Passage 3 below.
Questions 27-34
Reading Passage 3 has nine paragraphs, A-I.
Choose the correct heading for paragraphs B-I from the list of headings below.
Write the correct number, i-xi, in boxes 27-34 on your answer sheet.
List of Headings
i How to grow a rubber tree
ii Useful additions to an existing idea
iii Useful for making your coat waterproof
iv The first known uses
v Exporting new forests
vi Inspiration from a bumpy bicycle ride
vii How different is rubber nowadays?
viii New demand leads to dramatically escalating cost
ix Unpopular due to decay
x A good idea in principle
xi Many modern uses
Example     Answer
Paragraph A   xi
Natural Rubber
An exotic material
A Today, we take modern materials very much for granted, without knowing their origin or realising their versatility. Rubber, for example, is a vital component of cars, supplying traction between the wheels and the road, as well as sealing oil and fuel from leakage and absorbing unwanted vibrations from the engine. Rubber also supplies us with many domestic items (toy balloons, water bottles, condoms, carpet underlay, mattresses and cushioning), office products (rubber bands, erasers) and articles of sports and recreation (footballs, golf balls, tennis balls, etc.). But where does rubber come from?
B Natural rubber was discovered during the various invasions of South America by the Spanish conquistadors in the 15th century. The material, made simply by drying out the sap of a native tree, Hevea brasiliensis, was first spotted by Columbus in the West Indies in the 1490s, where it was used to made balls. It was also made into bags for carrying liquids by moulding flexible rubber sheet into the desired shape. Rubber was clearly a material well known to native cultures, and recent discoveries of its use in ancient ceremonies are hardly surprising.
C Despite its early discovery by the Spanish, it was not until about 1730 that rubber was introduced into Britain, and not until 1791 that its use for the mackintosh (the rubberised raincoat) was introduced. In 1770 Joseph Priestley, who also discovered oxygen, noticed that rubber erases pencil marks. Despite this serendipitous finding, it still took some time before the material was to find widespread application. One reason for this was its deterioration with time, degrading in air to a sticky unmanageable mess. That was to change dramatically with the invention of ’vulcanisation’, when, in 1834, Charles Goodyear found that cooking the material with raw sulphur stabilised it and stiffened products manufactured from the substance.
D This discovery opened the way to pneumatic tyres for early vehicles such as carriages (travel in which was rather painful owing to the rigid wheels and rough roads then in existence). The first patent for a tyre dates from 1846, when Robert Thompson announced the pneumatic tyre, a great advance for wheeled traffic. The key to the idea is the cushion provided by the air pocket, the pressure of which can be varied to suit the user. The invention languished, perhaps because of problems with containing the inevitable leaks of air from the many inner tubes. However, solid rubber tyres were subsequently adopted, with much reduced cushioning.
E At the same time, vulcanised rubber came to be used for an increasing number of products, such as galoshes or Wellington boots and improved mackintoshes, where rubber was combined with textile to make a waterproof fabric. The growing demand for natural rubber made it a commodity product, yet only supplied by one area in the world — Brazil. As a result, the price soared, creating rich entrepreneurs, who essentially exploited natives to collect the raw latex from the rainforest. But since the tree could potentially be grown in any tropical climate, why not collect seedlings and transplant to other countries?
F Intensive efforts were made at Kew Gardens to raise healthy plants from seeds collected by Sir Henry Wickham in Brazil in 1876. The young trees raised in the tropical greenhouse at Kew were shipped to Ceylon and Malaysia to form the nucleus of large plantations. Those countries were able to meet the rising demands of the rubber industry, and the price of raw rubber fell dramatically.
G In 1888, over forty years after Thompson’s invention of the pneumatic tyre, John Dunlop, a Belfast vet, responded to a request from his young son for better tyres for his trike. When ridden over the rough cobbles of Belfast’s streets, solid rubber tyres just could not give a comfortable ride. Various rubber tubes were used by vets, and Dunlop reinvented the pneumatic tyre by fitting a wheel with an inflated rubber tube protected by a heavier outer cover. After much experimentation, the world’s first bicycle tyre emerged.
H Dunlop’s first patent to protect the invention was inevitably invalid because of Thompson’s prior patent, but he went on to invent the valve and numerous other components which were proved valid. Those inventions were the base on which he and others built the bike tyre industry, which brought cycling into a new era for everyone. It was an era when industrial progress had created new-found wealth and leisure time for millions. As with any new and fundamental invention, the idea was taken up by others, in particular by Michelin in France (1896), to develop a much heavier-duty device, the car tyre.
I Today a wide range of synthetic rubber is available to designers, many for specialty tasks requiring, for example, very high or low temperatures. Yet natural rubber is still a valuable international commodity, helping many developing countries earn useful hard currency. The technology of processing the raw rubber has improved greatly over the years, but the basics still remain the same as they were when Kew Gardens selected the best plants for cloning and transplanting over one hundred years ago. [br] Paragraph D
选项
答案 x
解析 D段主要讲述1846年充气轮胎(pneumatic tyres)的发明，该发明刚开始时是轮式车辆的一大进步(a great advance)。之后第三句提到了其原理是依靠气袋提供缓冲力(the cushion provided by the air pocket)。但由于避免不了内胎漏气，充气轮胎却发展不起来(languished)，而之后出现硬质橡胶轮胎。综合来看，本段主要是论述充气轮胎的发明，及其发展不起来的原因。但各选项中并无出现与此相关的主题词，而x项的in principle可理解为“在理论上，按道理”，该项所说的“理论上的好主意”(暗示实际上行不通)正好是对充气轮胎的概括，虽然理论上很好，但避免不了漏气这一局限，最终发展不起来，故答案为x。
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