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The effects of air pollution on natural conditions have been a disturbing problem for many years. Some scientists hold the view that the air inside houses may be more dangerous than the air outside. It may even be one hundred times worse.

Most scientists agree that every modern house has some kind of indoor pollution, which can cause a person to feel tired, to suffer eye pain, headache and other problems. Believe it or not, some pollutants can cause breathing diseases of blood and even cancer.

What made us feel relieved is that there’s growing concern about the problem now. It is true that when builders began constructing houses and offices they did not want to waste energy. To do this they built buildings that prevented or limited the flow of air between inside and outside. For the same purpose, man-made building materials were employed to build houses, which are now known to let out some harmful gases.

Facing the serious challenge, scientists have been searching for a way to handle the problem. To everyone’s delight, they discovered a natural pollution control system for building—green plants, though they do not really know how plants control air pollution. Scientists suppose that a plant’s leaves absorb or take in the pollutants and in exchange gives out oxygen through its leaves and tiny organizations on its roots. Therefore they recommend that all buildings should have one large plant or several small plants inside for every nine square meters of space. Because studies indicate that different plants absorb different chemicals, the most effective way to clean the air is to use different kinds of plants. In conclusion, having green plants inside your house can make it a prettier and healthier place. Why not try?

1.Which of the following statements is TRUR?

2.According to scientists, some kind of indoor pollution can be found in ________.

3.What does the underlined part “To do this” refer to in Para3?

4.The reason why we should use different kinds of plants to clean the air is that ___.

A  volcanic eruption in Iceland has sent ash across northern Europe．Airlines have stopped or changed the flights across the Atlantic Ocean，leaving hundreds of passengers stuck in airports．

Grimsvotn is one of the largest and most active volcanoes in Europe．What makes Grimsvotn different is that it lies under a huge glacier（冰川）of ice up to 12 maters thick．The hot volcano heats up the ice above it，which then forms a layer（層）of water between the glacier and the volcano This layer of water puts pressure on the volcano，keeping it stable，As the water flows out from under the glacier，the pressure lifts．The lava（巖漿） from the volcano then comes up to the surface．This is exactly what happened today．

Now，airlines have to make changes to their flights so as not to fly through the clouds of volcanic ash．According to KLM，one of Europe's biggest airlines，airplanes cannot go under the cloud or over it．Going through the cloud can result in ash getting stuck in the airplane's engines，causing damage to the plane．

The eruption has also caused problems for animals in Iceland．The volcano left ash and sharp．Glass-like rocks all over the countryside．Farmers are keeping their animals inside to stop them from eating ash- covered grass to the sharp object．

1．What makes Grimsvotn different from other volcanoes?

A．It is below ice．                                         B．It lies under the sea．

C．It is the largest volcano．                                   D．Its lava affects the airlines．

2．What keeps Grimsvotn still?

A．The slow flow of water．                           B．The low water temperature．

C．The thick glacier．                                     D．The water pressure．

3．Which of the following is the result of the volcanic eruption?

A．People stop traveling in Europe．

B．Airlines suffer from the loss of planes．

C．It becomes dangerous for animals to eat outside．

D．Parmers have lost many of their animals．

4．This text is most probably taken from _________．

A．a research paper                                         B．a newspaper report

C．a class presentation                                     D．a geography textbook

  For years scientists have been worried about the effects of air pollution on the earth’s natural conditions. Some believe the air inside many houses may be more dangerous than the air outside. It may be one hundred times worse.
  Indoor air pollution can cause a person to feel tired, to suffer eye-pain, headache and other problems. Some pollutants（ 污染 物） can cause breathing disorders, diseases of blood and even cancer, Most scientists agree that every modern house has some kind of indoor pollution. People began to notice the problem in the early 1970s. It is that when builders began making houses and offices they did not waste energy. To do this they built buildings that limited the flow of air between inside and outside. They also began using manmade building materials. These materials are now known to let out harmful gases. As the problem became more serious, scientists began searching for a way to deal with it. They discovered a natural pollution control system for building― green plants. Scientists do not really know how plants control air pollution. They believe that a plant’s leaves absorb or take in the pollutants. In exchange the plant lets out oxygen through its leaves and through its tiny organizations on its roots. Scientists suggest that all buildings should have one large plant or several small plants inside for every nine square metres of space. Studies of different plants show that each absorbs different chemicals. So the most effective way to clean the air is to use different kinds of plants. Having green plants inside your house can make it a prettier and more healthy place.

  64．Generally speaking, indoor air pollution may be more harmful than the air outside because ________.
  A. the man - made building materials let out dangerous gases inside houses
  B. there may be more harmful gases outside houses
  C. the flow of air indoors is limited
  D. indoor air pollution can make a person seriously ill
  65．The indoor air pollution is caused________.
  A. by the building method through which the builders want to save energy
  B. by the limit of the flow of air between inside and outside
  C. by the building things which are made of man - made materials
  D. not only by the limit of air - flow but also by the man made materials
  66．The most effective way to clean the air is to use different kinds of plants because________.
  A. they may let out more oxygen which people need
  B. they can absorb different kinds of the harmful indoor chemicals
  C. they can take in all kinds of indoor pollutants
  D. they can make your house prettier and more healthy

For years scientists have been worried about the effects of air pollution on the earth’s natural conditions. Some believe the air inside many houses may be more dangerous than the air outside. It may be one hundred times worse.

Indoor air pollution can cause a person to feel tired, to suffer eye pain, headache and other problems. Some pollutants can cause breathing disorders, diseases of blood and even cancer. Most scientists agree that every modern house has some kind of indoor pollution.

People have paid more attention to the problem now. It is true that when builders began making houses and offices they did not waste energy. To do this they build buildings that limited the flow of air between inside and outside. They also began using man-made building materials. These materials are now known to let out harmful gases.

As the problem became more serious, scientists began searching for a way to deal with it. They discovered a natural pollution control system for building—green plants. Scientists do not really know how plants control air pollution. They believe that a plant’s leaves absorb or take in the pollutants. In exchange the plant lets out oxygen through its leaves and tiny organizations on its roots. Scientists suggest that all buildings should have one large plant or several small plants inside for every nine square meters of space. Studies of different plants show that each absorbs different chemicals. So the most effective way to clean the air is to use different kinds of plants. Having green plants inside your house can make it a prettier and more healthy place.

1.Generally speaking, indoor air pollution may be more harmful than the air outside because ______.

A．indoor air pollution can often make people seriously ill

B．man-made building materials give off dangerous gases

C．there may be more harmful gases outside the buildings

D．the air indoors is polluted, which is very harmful

2.Some kind of indoor pollution can be found　in______．

Ａ．every modern house　         B．every old house

C．all kinds of houses           D．all kinds of offices

3.The indoor air pollution is caused by ______.

A．the limit of the flow of air between inside and outside

B．the building way that the builders want to save energy

C．the building things that are made of man-made materials

D．the man-made building materials and the limit of air-flow

4.The reason why we should use different kinds of plants to clean the air is that ______.

A．plants can let out all kinds of pollutants indoors

B．plants may take in more oxygen which people need

C．plants can absorb all kinds of harmful indoor chemicals

D．plants can make our houses prettier and more healthy

For years scientists have been worried about the effects of air pollution on the earth’s natural conditions. Some believe the air inside many houses may be more dangerous than the air outside. It may be one hundred times worse.

Indoor air pollution can cause a person to feel tired, to suffer eye pain, headache and other problems. Some pollutants（污染物）can cause breathing disorders, diseases of blood and even cancer. Most scientists agree that every modern house has some kind of indoor pollution.

People have paid more attention to the problem now. It is true that when builders began making houses and offices they did not waste energy. To do this they build buildings that limited the flow of air between inside and outside. They also began using man-made building materials. These materials are now known to let out harmful gases.

As the problem became more serious, scientists began searching for a way to deal with it. They discovered a natural pollution control system for building—green plants. Scientists do not really know how plants control air pollution. They believe that a plant’s leaves absorb（吸收）or take in the pollutants. In exchange the plant lets out oxygen through its leaves and tiny organizations on its roots. Scientists suggest that all buildings should have one large plant or several small plants inside for every nine square meters of space. Studies of different plants show that each absorbs different chemicals. So the most effective way to clean the air is to use different kinds of plants. Having green plants inside your house can make it a prettier and more healthy place.

56. Generally speaking, indoor air pollution may be more harmful than the air outside because ______.

A．indoor air pollution can often make people seriously ill

B．man-made building materials give off dangerous gases

C．there may be more harmful gases outside the buildings

D．the air indoors is polluted, which is very harmful

57. Some kind of indoor pollution can be found in _______.

A．every modern house                                   B．every old house

C．all kinds of houses                                      D．all kinds of offices

58. The indoor air pollution is caused by ______.

A．the limit of the flow of air between inside and outside

B．the building way that the builders want to save energy

C．the building things that are made of man-made materials

D．the man-made building materials and the limit of air-flow

59. The reason why we should use different kinds of plants to clean the air is that ______.

A．plants can let out all kinds of pollutants indoors

B．plants may take in more oxygen （氧氣）which people need

C．plants can absorb all kinds of harmful indoor chemicals

D．plants can make our houses prettier.