Question

For years scientists have been worrying 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 built 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 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.

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

A．indoor air pollution can make a person 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 airflow

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

Answer

1.B

2.A

3.D

4.C

【解析】

试题分析：

1.细节理解题。第二段中下面两句可以说明问题“To do this, they built buildings that limited the flow of air between inside and outside.”“These materials are now known to let out harmful gases.”人造的建筑材料会释放出有害的气体，注意let out的含义与B选项中give off的含义相同。故选B。

2.细节理解题。由第二段最后一句“Most scientists agree that every modern house has some kind of indoor pollution. ”可知，室内污染存在于每个现代房屋中。故选A。

3.细节理解题。由第三段“To do this they built buildings that limited the flow of air between inside and outside. They also began using man-made building materials.”可知，室内人造建筑材料和封闭的室内空气流动环境造成了室内污染。故选D。

4.细节理解题。本文最后两句“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.”是说不同种类的植物让室内空气变得更加清新健康，换句话说就是能够吸收所有种类有害的室内化学气体。故选C。

考点：科教类阅读