2015年在职GCT英语备考：阅读理解专项训练(7)

　　In the early days of sea travel, seamen on long voyages lived exclusively on salted meat and biscuits. Many of them died of scurvy (坏血病), a disease of the blood which causes swollen gums, livid white spots on the flesh and general exhaustion. On one occasion, in 1535, an English ship arrived in Newfoundland with its crew desperately ill. The men’s lives were saved by Iroquois Indians who gave them vegetable leaves to eat. Gradually it came to be realized that scurvy was caused by some lack in the sailors’ diet and Captain Cook, on his long voyages of discovery to Australia and New Zealand, established the fact that scurvy could be warded off by the provision of fresh fruit for the sailors.

　　Nowadays it is understood that a diet which contains nothing harmful may yet result in serious disease if certain important elements are missing. These elements are called “vitamins”. Quite a number of such substances are known and they are given letters to identify them, A, B, C, D, and so on. Different diseases are associated with deficiencies of particular vitamins. Even a slight lack of Vitamin C, for example, the vitamin most plentiful in fresh fruit and vegetables, is thought to increase significantly our susceptibility (敏感度) to colds and influenza.

　　The vitamins necessary for a healthy body are normally supplied by a good mixed diet, including a variety of fruit and green vegetables. It is only when people try to live on a very restricted diet, say during extended periods of religious fasting (斋戒), or when trying to lose weight, that it is necessary to make special provision to supply the missing vitamins.

　　11. Scurvy is a disease that is provoked by ____

　　A. salted meat and biscuits B. exhaustion

　　C. want of some essential substances D. lack of fresh vegetables and fruits

　　12. In the last sentence of Paragraph 1, “warded off” could probably be replaced by ____.

　　A. got rid of B. killedC. avoided D. cleared away

　　13. To avoid such disease as scurvy, it’s better for us ____.

　　A. not to eat much salted meatB. to supplement our diet with various vitamin pills

　　C. to have more fresh fruit and vegetablesD. to develop a good dietary habit

　　14. Based on the passage we can safely conclude that if our diet is not comprehensive enough ____.

　　A. vitamin pills are of no availB. nutritious food might be unhealthy

　　C. vegetable leaves can be a good remedyD. religious fasting may help out a lot

　　15. Which of the following sentences best expresses the central ideal of the passage?

　　A. Deficiencies of Vitamin C may cause serious diseases.

　　B. Fresh fruit and green vegetables contain enough nutrition that is necessary for a healthy body.

　　C. Vitamins play a vitally important role in people’s health.

　　D. A good mixed diet normally supplies sufficient vitamins for us.

　　11.【答案】C。

　　【解析】对于scurvy(败血症)整个第一段都在介绍其情况，是什么引起它的呢?这就要求读者对这一段的各细节都准确理解，文中很明确地提到败血症是由于水手的饮食中缺少一些东西而引起的，而败血症又可通过吃新鲜蔬果而避免，这是否意味着败血症是由于缺少新鲜蔬果而引起的呢?从字面看，似乎是正确的，有的读者会选D项，但我们仔细理解每一选项及原文，新鲜蔬果为什么能避免败血症，当然是由于其中含有丰富的维生素，从下文主要讲述的对象——维生素来看，我们也可猜到，真正引起败血症的是缺乏蔬果中的维生素，所以C项者是最准确的。

　　12.【答案】C。

　　【解析】用一个词或短语代替另一个词或短语，也是对词义的考查，通常可以从上下文来推断，既然败血症的产生原因已被查明，那么通过提供新鲜蔬果败血症当然能被“避免”。A项的除掉显然不正确，因为防治败血症可以通过多吃蔬果，但要除掉一种病症却不是那么简单的事。B项“杀死”，这与A项意思基本相似，也是不正确的。C项“避免”这与原文相符。D项“清除”这也与A、B两项相近，是不正确的。

　　13.【答案】D。

　　【解析】如何避免败血症的方法，文中已提到，可通过多吃新鲜蔬果的方法，正如第一题一样，透过表面文字新鲜蔬果的真正意义是什么?当然是指水手们单一的腌肉饮食太不合理，要补充蔬果以增加维生素，也就是说需要合理的饮食习惯，这样在仔细理解原文和选项后，我们不难发现D项是最合适的答案。

　　14.【答案】B。

　　【解析】这一题需要我们对全文都理解后才能得出答案，如果我们的食物摄取不够广泛会如何?A项“维生素丸没有用”，而文中未曾提到维生素丸的作用，而根据常识服食维生素丸是可以补充暂时的维生素不足的，因此A不正确。B项“有营养的食物也可能是不健康的”，正如文中提到的腌肉，虽然腌肉也有营养，但只吃咸肉而没有足够的维生素，水手们依然患了败血症，第二段第一句也表达了此意，因此B项是正确的。C项“蔬菜叶子可以作为一味好药”，如果食物摄取不广泛，蔬菜叶子并不能作万能的药，在文中它只适合于败血症的治疗，所以C项不准确。D项“宗教式的斋戒会很有帮助”，而文中提到，在进行斋戒时需要特别补充某些缺乏的维生素，所以D项不正确。

　　15.【答案】C。

　　【解析】这一题是读者对全文中心的理解，文章以败血症开篇引出维生素的重要性，末尾也提到了维生素的摄取途径，而这些都是为了突出维生素的重要性服务的。因此这篇文章的中心在于讲述维生素的重要性，所以应选C项。

本文选自新东方在线论坛。