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 (牙龈), 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 prevented by the supply 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 shortages 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 supply to make up for the missing vitamins.
57. Scurvy is a disease that is caused by ____
A. salted meat and biscuits B. exhaustion
C. lack of some essential substances D. need of fresh vegetables and fruits
58. To avoid such disease as scurvy, it’s better for us ____.
A. not to eat much salted meat
B. to supply our diet with various vitamin pills
C. to have more fresh fruit and vegetables
D. to develop a good dietary habit
59. Based on the passage we can safely conclude that if our diet is not comprehensive (广泛) enough, ____.
A. vitamin pills are of no use
B. nutritious food might be unhealthy
C. vegetable leaves can be a good treatment
D. religious fasting may help out a lot
60. Which of the following sentences best expresses the main idea of the passage?
A. Shortages 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.
CDBC
健康环保累阅读概念：
健康环保类文章常是介绍科学知识、生活常识和环境保护方面的短文。体裁有记叙文、 说明文、议论文和各种应用文。
健康环保类文章阅读技巧：
健康环保类文章常是介绍科学知识、生活常识和环境保护方面的短文。阅读此类短文要以现象或事物为中心进行思考，理解现象产生的原因、条件和客观规律等。同时要抓住事物的特征、用途和相互关系等。科普环保类文章一般为说明文，从结构上看大致可分为三个部分：
第一部分一般是文章的首段，主要用来提出文章的主题，即文章想要阐述、说明的主要内容；
第二部分是文章的主体，可由若干个段落组成，对文章的主题进行展开说明；
第三部分是结尾段，对文章的主题进行归纳总结。这类文章多用一般现在时，而且一般多使用客观性词语表述。有时为了强调客观性，也常使用被动语态。
从近几年的考试题来看，科普环保类的文章越来越与人们的实际生活相接近。由于此类文章缺乏故事情节，很多同学对此类文章感到费解。但一般的科普类文章都是就事论事，需要逻辑推理和想象的时候较少，因此此类阅读题也没有同学们想象中的那么难，只要多加训练，就能较好地答题。
【阅读策略】
1、概要(Summarizing)：
阅完材料后，将所阅材料浓缩，摘要，做出所阅材料的书面或口头梗概。
2、组织(Organization)：
阅读后根据阅读内容，识别观点、人物、事件之间的关系以及文章的结构关系。如：时间关系、比较或对比关系、相关关系及因果关系等。
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A. The effects of flu and its symptoms B. Types of virus to cause flu C. People’s attitudes toward flu D. The cause of flu E. The way that flu spreads F. The methods to fight flu |
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Flu (which is short for influenza) is a highly infectious disease, the cause of which is a very tiny organism known as a virus. Several types of flu are recognized, depending on the type of virus that causes the disease.
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Flu can often cause problems in breathing, and general infection of the lung. With elderly and weak people, these added complications often produce serious results. The virus, if not properly treated, can weaken the body so that patient may develop more serious illnesses, such as pneumonia and bronchitis. When people catch flu, they often complain of a headache or a sore throat. They usually have a fever and their temperature rises from the normal 37℃ (98.6) to about 39.5℃ (103). Sometimes a person has a dry hacking cough and aching joints.
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Today many doctors use drugs that fight the disease. And scientists have also developed vaccines that help to prevent it. If the patient has proper treatment, and complete rest in bed, the virus is normally beaten within a week to ten days.
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How does flu spread so quickly? When the infected person breathes out, sneezes or coughs, he gives out droplets of moisture in the breath from his mouth or nose. These remain in the air for some time. Flu viruses are present in these droplets. If a person sneezes in a crowd or poorly ventilated place, such as a lift, viruses can easily be carried from an infected person to a healthy person. This is known as droplet infection. The healthy person will breathe in the viruses given out by the infected person.
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There are three main types of virus that cause flu, which are called type A, B and C. type A is the most powerful of the three, and undergoes minor changes in its genetic material every few years. The new form of the virus is called a strain. The new strain is not affected by the current vaccines. It is said to be “resistant” to them. So doctors must be continually producing new vaccines to combat the new strains of virus.