剑桥雅思9阅读：Test2雅思阅读PASSAGE2真题+答案+解析

　　Passage2

　　Tidal Power

　　Undersea turbines which produce electricity from the tides are set to become an important source of renewable energy for Britain. lt is still too early to predict the extent of the impact they may have , but all the signs are that they will play a significant in the future

　　A Operating on the same principle as wind turbines, the power in sea turbines comes from tidal currents which turn blades similar to ships' propellers, but, unlike wind, the tides are predictable and the power input is constant. The technology raises the prospect of Britain becoming self-sufficient in renewable energy and drastically reducing itscarbon dioxide emissions. If tide, wind and wave power are all developed. Britain would be able to close gas, coal and nuclear power plants and export renewable power to other parts of Europe. Unlike wind power, which Britain originally developed and then abandoned for 20 years allowing the Dutch to make it a major industry, undersea turbines could become a big export earner to island nations such as Japan and New Zealand.

　　B Tidal sites have already been identified that will produce one sixth or more of the UK's power - and at prices competitive with modem gas turbines and undercutting those of the already ailing nuclear industry.One site alone, the Pentland Firth, between Orkney and mainland Scotland, could produce 10% of the country's electricity with banks of turbines under the sea, and another at Alderney in the Channel Islands three times the 1,200 megawatts of Britain's largest and newest nuclear plant, Sizewell B, in Suffolk. Othep sites identified include the Bristol Channel and the west coast of Scotland, particularly the channel between Campbeltown and Northern Ireland.

　　C Work on designs for the new turbine blades and sites are well advanced at the University of Southampton'ssustainable energy research group. The first station is expected to be installed off Lynmouth in Devon shortly to test the technology in a venture jointly funded by the department of Trade and Industry and the European Union. AbuBakr Bahaj, in charge of the Southampton research, said: The prospects for energy from tidalcurrents are far better than from wind because the flows of water are predictable and constant. The technology for dealing with the hostile saline environment under the sea has been developed in the North Sea oil industry and much is already known about turbine blade design, because of wind power and ship propellers. There are a few technical difficulties, but I believe in the next five to ten years we will be installing commercial marine turbinefarms. Southampton has been awarded £215,000 over three years to develop the turbines and is working with Marine Current Turbines, a subsidiary of IT power, on the Lynmouth project. EU research has now identified 106potential sites for tidal power, 80% round the coasts of Britain. The best sites are between islands or around heavily indented coasts where there are strong tidalcurrents.

　　D A marine turbine blade needs to be only one third of the size of a wind generator to produce three times as much power. The blades will be about 20 metres indiameter, so around 30 metres of water is required.Unlike wind power, there are unlikely be environmental objections. Fish and other creatures are thought unlikely to be at risk from the relatively slow-turning blades. Eachturbine will be mounted on a tower which will connect to the national power supply grid via underwater cables. The towers will stick out of the water and be lit, to warn shipping, and also be designed to be lifted out of the water for maintenance and to clean seaweed from the blades.

　　E Dr Bahaj has done most work on the Alderney site, where there are powerful currents. The single underseaturbine farm would produce far more power than needed for the Channel Islands and most would be fed into the French Grid and be re-imported into Britain via the cable under the Channel.

　　F One technical difficulty is cavitation, where low pressure behind a turning blade causes air bubbles. These can cause vibration and damage the blades of the turbines. Dr Bahaj said: ‘We have to test a number of blade types to avoid this happening or at least make sure it does not damage the turbines or reduce performance.Another slight concern is submerged debris floating into the blades. So far we do not know how much of a problem it might be. We will have to make the turbines robustbecause the sea is a hostile environment, but all the signs that we can do it are good.'

　　Question 14

　　答案: C

　　关键词: first test site

　　定位原文: C 段第 2 句“The first station is…”第 一个潮汐发电站预计很快将在德文郡的林茅斯海岸建立，用来检测贸易与工业部和欧盟的一个合资项目研发的技术。

　　解题思路: 题干中的 first test 两个词都直接对应这句话中的 first...test; 而题干中的 site 对应原文的 Lynmouth in Devon, 表示测试站的地点。

　　Question 15

　　答案: E

　　关键词: back into Britain

　　定位原文: E 段第 2 句“The single undersea turbine farm…”

　　解题思路: 仅仅这一个水下涡轮机群的发电量就远比海峡群岛所需要的电量还要多，其中大部分电量将运输到法国电网，然后通过水下电缆重新进入英国。 题干中的 back into Britain 对应原文中的...be re-imported into Britain via the…

　　Question 16

　　答案：A

　　关键词：previous, alternative source of energy

　　定位原文：A 段最后一句“Unlike wind power which Britain…” 与之前开发风能有所不同，风能由英国首先开发，而后却搁置了 20 年，最后由荷兰将其发展成一个主要产业，这次通过向日本与新西兰这样的岛国出口水下涡轮机，英国将赚取巨额外汇。

　　解题思路: 题干中的previous对应这句话中的Unlike...0riginany, 为了突出这次潮汐发电的前景，这句话提到了之前英国对风能进行尝试开发，但却半途而废，被荷兰发展壮大。

　　Question 17

　　答案：C

　　关键词：technology, another industry

　　定位原文：C 段第 4 句“The technology for dealing with…” 应对海底恶劣盐渍环境的技术已经在北海油田工业中得以研发，而且人们对涡轮机叶片的设计已经有了了解。

　　解题思路：题目中的 another industry 对应这句话中的 the North Sea oil industry，属于同义表达。

　　Question 18-Question 22

　　答案: A, D, E, F,J (in any order)

　　关键词：claims about tidal power are made by the writer

　　定位原文：指定多选，参见解题思路

　　解题思路: 选项 A(A 段第 1 句)题干中 more reliable source of energy(更可靠的能源)对应这句话中的...are predictable and the power input is constant, 表明潮汐能源具备风能所没有的两个优点：可预测的，恒定的;选项 B，过于绝 对，不选;选项 C，文中完全未提及;选项 D(A 段第 2 句)二氧化碳的排放量下降了，自然也减少了空气污染;选项 E(A 段第 3 句)题干中的 contribute to the closure of many existing power stations 对应文中 的… dose gas, coal and nuclear power plants…;选项 F(A 段最后一句)，题干中的 national income 对应原文中的 earner (意为 a business or activity which makes a profit);选项 G、 H、I，文中完全未提及;选项 J(C 段倒数第二句)题干中 best produced in the vicinity of coastlines 对应这句话中的 The best sites are between...。

　　Question 23

　　答案: maintenance

　　关键词：and, seaweed

　　定位原文：D 段最后一句“..and also be designed…seaweed from the blades.”

　　解题思路：空格中的词应该和定位词 seaweed 构成并列关系，且出现在 and 之前，同时可预测词性为名词。此外，因为题干中的 raised 可同义替换成原文 lifted, 故符合要求的只有 maintenance, 意思为：整个机塔可以露出水面，以便维护叶片以及清理其中的海藻。

　　Question 24

　　答案：slow-turning

　　关键词：due to, sea life not in danger, blades

　　定位原文：D 段第 4 句“Fish and other creatures are…”

　　解题思路：空格前有 due to，可预测需要填表示原因的词。再进一步分析，空格前是副词，因而空格要填的是形容词。题干中 sea life not in danger 对应原文 creatures unlikely to be at risk(海洋生物不会面临危险)，原因是叶片转速相对较低，所以 slow-turning 为备选。同时，题干中 comparatively 可同义替换原文中的 relatively，所以备选答案被验证，此空应该填 slow-turning。

　　Question 25

　　答案：low pressure

　　关键词：result from, behind blades

　　定位原文：F 段第 1 句“One technical difficulty is…”

　　解题思路：空格里应该填名词，表原因，并且是出现在定 位词 behind, blades 之前，包含定位词的这句话中可能是答案的有两个名词：cavitation，low pressure。题干中的 result from 对应原文中的 cause,而能够形成紧密因果关系的是 low pressure, 之前的 cavitation 是这种技术难题的名称。整个题干的意思为：叶片后方由于气压低而产生气泡。这种技术难题被称做空化。所以 25 题答案为 low pressure，26 题答案为 cavitation。

　　Question 26

　　答案：cavitation

　　关键词：known as

　　定位原文：F 段第 1 句“One technical difficulty is…”

　　解题思路：参考 25 题分析。题干 known as 对应原文中...is...