查看汇总:
Recent research has claimed that an excess of positive ions in the air can have an ill effect on peoples physical or psychological health. What are positive ions? Well, the air is full of ions, electrically charged particles, and generally there is a rough balance between the positive and the negative charged. But sometimes this balance becomes disturbed and a larger proportion of positive ions are found. This happens naturally before thunderstorm, earthquakes when winds such as the Mistral, Hamsin or Sharav are blowing in certain countries. Or it can be caused by a build-up of static electricity indoors from carpets or clothing made of man-made fibres, or from TV sets, duplicators or computer display screens.
When a large number of positive ions are present in the air many people experience unpleasant effects such as headaches, fatigue, irritability, and some particularly sensitive people suffer nausea or even mental disturbance. Animals are also affected, particularly before earthquakes, snakes have been observed to come out of hibernation, rats to flee from their burrows, dogs howl and cats jump about unaccountably. This has led the US Geographical Survey to fund a network of volunteers to watch animals in an effort to foresee such disasters before they hit vulnerable areas such as California.
Conversely, when large numbers of negative ions are present, then people have a feeling of well-being. Natural conditions that produce these large amounts are near the sea, close to waterfalls or fountains, or in any place where water is sprayed, or forms a spray. This probably accounts for the beneficial effect of a holiday by the sea, or in the mountains with tumbling streams or waterfalls.
To increase the supply of negative ions indoors, some scientists recommend the use of ionisers: small portable machines, which generate negative ions. They claim that ionisers not only clean and refresh the air but also improve the health of people sensitive to excess positive ions. Of course, there are the detractors, other scientists, who dismiss such claims and are skeptical about negative/positive ion research. Therefore people can only make up their own minds by observing the effects on themselves, or on others, of a negative rich or poor environment. After all it is debatable whether depending on seismic readings to anticipate earthquakes is more effective than watching the cat.
1.What effect does exceeding positive ionization have on some people?
A.They think they are insane.
B.They feel rather bad-tempered and short-fussed.
C.They become violently sick.
D.They are too tired to do anything.
2.In accordance with the passage, static electricity can be caused by___.
A.using home-made electrical goods.
B.wearing clothes made of natural materials.
C.walking on artificial floor coverings.
D.copying TV programs on a computer.
3.A high negative ion count is likely to be found___.
A.near a pound with a water pump.
B.close to a slow-flowing river.
C.high in some barren mountains.
D.by a rotating water sprinkler.
4.What kind of machine can generate negative ions indoors?
A.Ionisers.
B.Air-conditioners.
C.Exhaust-fans
D.Vacuum pumps.
5.Some scientists believe that___.
A.watching animals to anticipate earthquakes is more effective than depending on seismography.
B.the unusual behavior of animals cannot be trusted.
C.neither watching nor using seismographs is reliable.
D.earthquake
答案:BCDAA
雅思听力选择题的答题方法
雅思听力的三大审题技巧
雅思听力常用高频短语30个
突破雅思听力高分的有效方法
解读雅思听力的数字考点
雅思听力冷凝法讲解
如何突破雅思听力部分?
雅思听力提速技巧:关键信息点
雅思听力提高以词汇语法为基础
如何克服雅思听力中的四大障碍
雅思听力可以利用材料反复精听
雅思听力Section 4填空题答题技巧
攻破雅思听力高频词汇的必杀技
雅思听力常考场景词汇
短期提高雅思听力分数的秘诀
雅思听力中的语法短语练习
雅思听力各类题型解题指导
雅思听力填空题的解题技巧
雅思听力的十大常见错误类型
如何掌控语音突破雅思听力?
雅思听力语音不全的解决办法
提高雅思听力反应速度的方法
轻松拿下雅思听力的五个环节
雅思听力考前需要注意的重点
雅思听力练习的三原则和四个字
雅思听力中的经典场景总结
实例解析雅思听力中的大陷阱
30个雅思听力考试的常用短语
雅思听力与英文发音的关系
浅谈雅思听力关系词的妙用
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |