题目内容
Snow-melting Agent
A heavy snow can kill pests and this means a good harvest next year.This will bring as well as trouble to urbanites.
On Nov.16,2003,a cold air current brought a heavy snow to Beijing.To prevent traffic jams,related government departments mobilized people to clear off snow on streets.
One of the most effective ways to clear off snow on roads is to scatter snow-melting agent on the roads.The major component of the snow-melting agent is salt.The snow-melting agent can make snow stop from freezing,make it easier to clear off the road,and allow traffic to flow smoothly.But it also brings about some hidden dangers.In the spring of 2003,over 300 000 trees in Beijing urban districts died.After analyzing soil around these trees,experts discovered that the salt content of these soils was 392 times higher than normal.Where did the excessive salt come from?After investigating,forestry experts found that when clearing snow in the winter,people usually heap snow containing snow-melting agent at trees’ roots,and that when the snow melts,this agent penetrates the soil and increases its salt content.The snow-melting agent indirectly killed the trees.
Statistics show that during a heavy snow in 2002,over 1000 tons of snow-melting agent was scatterred on streets in Beijing.Snow water containing a large amount of snow-melting agent got into the soil through sewers.
In addition,salt in the snow-melting agent can expedite the corrosion of steel bars in concrete buildings and cause the concrete to crack and peel,shortening the life of roads.
Scientists and government officials are required to solve traffic problems caused by heavy snows as soon as possible and at the same time try to reduce the negative effects of the snow-melting agent.This is a difficult problem placed before them.Related authorities have framed some local criteria to regulate the production and use of snow-melting agents.
Now,more harmless snow-melting agents are being developed.Now that even snow-melting agents that meet today’s criteria must still be used carefully,we have to rely more on our manpower and machines to clear off snow.
This year,in addition to using snow-melting agents,Beijing will use a large number of snow vehicles to clear snow on roads.In more places,citizens are mobilized to clear snow with their hands.This may be a test of a city’s civilization level.
小题1:Salt is a snow-melting agent while _________ is a cleaning agent.
小题2:The third paragraph of the text is mainly about _______.
小题3:According to the text,the most practical way to clear off snow is to _________.
小题4:This text most probably appears in_________.
A heavy snow can kill pests and this means a good harvest next year.This will bring as well as trouble to urbanites.
On Nov.16,2003,a cold air current brought a heavy snow to Beijing.To prevent traffic jams,related government departments mobilized people to clear off snow on streets.
One of the most effective ways to clear off snow on roads is to scatter snow-melting agent on the roads.The major component of the snow-melting agent is salt.The snow-melting agent can make snow stop from freezing,make it easier to clear off the road,and allow traffic to flow smoothly.But it also brings about some hidden dangers.In the spring of 2003,over 300 000 trees in Beijing urban districts died.After analyzing soil around these trees,experts discovered that the salt content of these soils was 392 times higher than normal.Where did the excessive salt come from?After investigating,forestry experts found that when clearing snow in the winter,people usually heap snow containing snow-melting agent at trees’ roots,and that when the snow melts,this agent penetrates the soil and increases its salt content.The snow-melting agent indirectly killed the trees.
Statistics show that during a heavy snow in 2002,over 1000 tons of snow-melting agent was scatterred on streets in Beijing.Snow water containing a large amount of snow-melting agent got into the soil through sewers.
In addition,salt in the snow-melting agent can expedite the corrosion of steel bars in concrete buildings and cause the concrete to crack and peel,shortening the life of roads.
Scientists and government officials are required to solve traffic problems caused by heavy snows as soon as possible and at the same time try to reduce the negative effects of the snow-melting agent.This is a difficult problem placed before them.Related authorities have framed some local criteria to regulate the production and use of snow-melting agents.
Now,more harmless snow-melting agents are being developed.Now that even snow-melting agents that meet today’s criteria must still be used carefully,we have to rely more on our manpower and machines to clear off snow.
This year,in addition to using snow-melting agents,Beijing will use a large number of snow vehicles to clear snow on roads.In more places,citizens are mobilized to clear snow with their hands.This may be a test of a city’s civilization level.
小题1:Salt is a snow-melting agent while _________ is a cleaning agent.
| A．water | B．soap | C．a washing-machine | D．a housewife |
| A．the side effect of snow-melting agent |
| B．a case of damage to trees caused by snow-melting agent |
| C．the results of using snow-melting agent |
| D．the uses of snow-melting agent |
| A．use snow-melting agent as much as possible |
| B．only use more harmless snow-melting agent |
| C．encourage people to clear snow with their hands |
| D．use more snow vehicles |
| A．a newspaper | B．a magazine on latest findings |
| C．a book on salt | D．a magazine on environmental protection |
小题1:B
小题2:C
小题3:C
小题4:D
小题1:通过类比猜词义。
小题2:从第三段第三句和第四句可知。
小题3:从最后一段第二句和倒数第二段第二句可知。
小题4:概括主题，推断出处。
练习册系列答案
名校通行证有效作业系列答案
相关题目
people in Europe began to 
that mountains were beautiful. 
that time, mountains were feared by the people 
on the plain, especially by the city people, 
they were wild and 
places 
one was easily 
or killed by terrible animals.
people 
comfortably in the towns began to grow 
them. They began to feel 
looking for wild excitement, as their attention turned from the man-made town to the 
country; and to places 
dangerous and wild. So high mountains began to be 
for a holiday.
To some people, there is something 
about getting to the 
of a high mountain: a struggle against nature is finer than a battle 
other human beings. And after a difficult climb, what a 
reward it is to look down on everything within sight.