第三篇
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
第三篇答案BCDAA
沪教版小学英语一年级下册教案unit1课时6
牛津版一年级英语上册unit5 Fruit教案(2)
牛津版一年级英语上册Unit 2 Good morning 教案
上海版牛津一年级英语教案Unit8 Playtime(总五课时)
上海牛津版一年级英语下册Unit2 Small animals第五课时教案
一年级英语上册Unit1 My classroom第三课时教案
新起点小学一年级英语下册Unit11 Toys教案
上海版牛津一年级英语教案 Unit 3 My abilities
小学一年级英语下册Unit2 Small animals教案1
新课标小学英语第一册期末考试百词范围
一年级英语上册教案 Unit1My classroom 第三课时
上海牛津版一年级英语下册Unit2 Small animals教案
牛津版一年级英语上册教案Unit4 My bag第一课时
牛津版一年级英语上册unit5 Fruit教案(3)
苏教版牛津小学一年级英语教案Unit1 What`s your name
一年级英语教案Module1 unit6 Mid-Autumn Festival
牛津版小学一年级英语上册Unit1 Hello教案
一年级英语下册Unit2 Small animals第三课时教案
一年级英语上册教案 Unit 1 Period 1
新起点小学一年级英语教案Unit7 Fruit
沪教牛津版小学英语一年级上册 Unit 8 教案
上海牛津版一年级英语下册Unit3 Colours教案(1)
沪教牛津版一年级英语上册教案Unit1 My classroom第二课时
一年级英语上册教案 Unit 1 第二课时
沪教牛津版小学英语一年级上册 Unit3 period2教案
沪教版小学英语一年级下册教案unit1课时1
沪教版小学英语一年级下册教案unit1课时5
沪教版小学英语一年级下册教案unit1课时4
上海牛津版一年级英语下册Unit9 Revision第二课时教案
沪教版小学英语一年级下册教案unit1单元分析
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |