2020军队历年真题：职称英语《综合A》补全短文练习及答案二

The Tough Grass that Sweetens Our Lives

　　Sugar cane was once a wild grass that grew in New Guinea and was used by local people for roofing their houses and fencing their gardens. Gradually a different variety evolved which contained sucrose (蔗糖) and was chewed on for its sweet taste. Over time, sugar cane became a highly valuable commercial plant, grown throughout the world. __________ (46)

　　Sugar became a vital ingredient in all kinds of things, from confectionery (糖果点心 ) to medicine, and, as the demand for sugar grew, the industry became larger and more profitable.

　　__________ (47) Many crops withered( 枯萎)and died, despite growers' attempts to save them, and there were fears that the health of the plant would continue to deteriorate.

　　In the 1960s, scientists working in Barbodos looked for ways to make the commercial species stronger and more able to resist disease. They experimented with breeding programmes, mixing genes from the more delicate, commercial type. __________(48) This sugar cane is not yet ready to be sold commercially, but when this happens, it is expected to be incredibly profitable for the industry.

　　__________(49) Brazil, which produces one quarter of the world's sugar, has coordinated an international project under Professor Paulo Arrudo of the Universidade Estaudual de Campinas in Sao Paulo. Teams of experts have worked with him to discover more about which parts of the genetic structure of the plant are important for the production of sugar and its overall health.

　　Despite all the research, however, we still do not fully understand how the genes function in sugar cane __________ (50) This gene is particularly exciting because it makes the plant resistant to rust, a disease which probably originated in India, but is now capable of infecting sugar cane across the world. Scientist believes they will eventually be able to grow a plant which cannot be destroyed by rust.

　　A. Eventually, a commercial plant was developed which was 5 percent sweeter than before,but also much stronger and less likely to die from disease.

　　B. One major gene has been identified by Dr Angelique D'Hont and her team in Montpelier,France.

　　C. Sugar cane is now much more vigorous and the supply of sugar is therefore more

　　guaranteed.

　　D. Since the 1960s, scientists have been analyzing the mysteries of the sugar cane's genetic code.

　　E. The majority of the world's sugar now comes from this particular commercial species.

　　F. Unfortunately, however, the plant started to become weaker and more prone to disease.

　　

46.E。空格前一句甘蔗成了一种极具价值的商业作物，在全世界种植。空白处应继续谈论其价值，故E选项(现在世界上大部分糖都是产自这个特殊的商业作物)符合文意。

　　47.F。空格前提到对糖的需求增加，这个行业开始获利，而空格后提到植物枯萎并死掉。前后具有转折关系，所有选项中只有F含有转折词however，故F(然而不幸的是这种植物开始变弱，变得容易得病)是正确答案。

　　48.A。空格前提到了科学家进行不同植物基因混合的实验来培育新品种，空格后提到现在这种甘蔗植物还不准备用作商业用途。由此可知，空白处讲的应该是关于新的甘蔗品种，故A(最终，一种新的商业甘蔗被培养出来，比之前的甜度增加5%，而且比之前的作物要更强壮，发病的可能性更小)是正确答案。

　　49.D。空格后列举了巴西的例子，指出科学家试图发现更多的影响含糖量和产量的基因结构，故D项(自20世纪60年代起，科学家一直在研究甘蔗基因代码的秘密)是正确答案。

　　50.B。空格前提到研究者们仍然无法完全了解甘蔗的基因，空格后提到这个基因尤其令人兴奋，其中的this gene应该指代空白处提到的某个基因，故B选项(一个主要的基因已经由Angellique D’Hont博士及其团队鉴别出来了)符合文意。