题目内容
These days we hear a lot about how air pollution is changing temperatures on the earth. New evidence from a mountaintop in China now suggests that pollution can also change the amount of rain and snow that falls in some places.
Usually, more rain falls in mountainous places than in flat areas upwind from the mountains. That’s because air can hold a lot of water. When wind blows wet air up a mountainside, the air gets colder. This temperature change often forces water to fall as rain or snow.
In recent years, however, many mountainous areas in the western United States have been getting less rain than normal. Mountains that are downwind from cities have experienced the biggest drops.
Some scientists have theorized（推理）that pollution drifts （趋势）from the cities into the mountains, affecting rainfall, but proving this link has been difficult.
Searching for answers, a team led by a scientist from the Hebrew University went to s mountain in China called Mount Hua, which is 2,060 meters tall and lies about 120 kilometers east of the Chinese city Xi’an. Since 1954, scientists have been collecting details about rainfall, humidity（湿度）, and visibility（能见度）in the area.
Using this data, the scientists compared rainfall on Mount Hua to rainfall in the nearest city, Huayin, on days with different levels of visibility. When the air was clear and people could see as far as 20 km, the scientists found that 65% more rain fell on the mountain than in the city.
But when the air was smoggy, allowing only 8 km of visibility through the mist, the mountain received just 20% more rain than the city. The new data supports the theory that pollution affects rainfall.
Some scientists believe that there are other explanations for the numbers. It’s possible, for example, that natural particles（微粒）in the air, rather than particles produced by pollution, are affecting visibility.
According to the 1st paragraph, air pollution is changing the following EXCEPT ______.
A．the temperature B．the amount of rain
C．the habit of eating D．the amount of snow
According to the passage, what will probably happen when the wet air in the sky gets colder?
A．It will probably rain or snow B．It will probably be cloudy.
C．It will probably wind D．It will probably become dry.
Why did the team led by a scientist go to Mount Hua?
A．They wanted to pay a visit to Mount Hua.
B．They wanted to collect the data for their theory.
C．They wanted to measure Mount Hua.
D．They wanted to have a good rest on Mount Hua.
You can most probably read the passage in _______.
A．a travel guide
B．a telephone book
C．a cartoon book
D．a science book
【小题1】C
【小题2】A
【小题3】B
【小题4】D
解析:
【小题1】从第一段提供的信息可知，air pollution正在改变全球temperature、the amount of rain and snow。所以选项Ｃ是正确答案。）
【小题2】从第二段中的句子“When wind blows wet air up a mountainside, the air gets colder. This temperature change often forces water to fall as rain or snow.”可知，A是正确答案。）
【小题3】从第五段提供的信息可知，B是正确答案。）
【小题4】本文讲述的是科学家们的研究结果，所以最有可能出现在a science book里。）
应用题点拨系列答案
状元及第系列答案
同步奥数系列答案第四部分：写作
第一节： ( 共10小题，每小题1分，共10分 )
读下面一篇文章，根据文中信息完成所给表格，每空不超过三个单词。
People in the United States honor their parents with two special days: Mother’s Day, on the second Sunday in May, and Father’s Day, on the third Sunday in June. These days are set aside to show love and respect for parents. They raise their children and educate them to be responsible citizens. They give love and care. These two days offer a chance to think about the changing roles of mothers and fathers. More mothers now work outside the home. More fathers must help with child-care.
These two special days are celebrated in many different ways. On Mother’s Day people wear carnations. A. red one stands for a living mother. A. white one shows that the mother is dead. Many people attend religious services（宗教仪式）to honor parents. It is also a day when people whose parents are dead visit their graves. On these days, families get together at home and in restaurants. They often have outdoor BBQs for Father’s Day. These are days of fun and good feelings and memories.
Another tradition is to give cards and gifts. Children make them in school. Many people make their own presents. These are valued more than the ones bought in stores. It is not the value of the gift that is important, but it is “the thought that counts”. Greeting card stores, florists, candy makers, bakeries, telephones companies and other stores do a lot of business during these holidays.
71.
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Types/ categories |
●Mother’s Day ●72. |
|
73. |
to show love and respect for parents. |
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Common points |
offer a chance to think about74. |
|
75. |
● wearing carnations on Mother’s Day. ●76. to honor parents. ●77. ●78. at home and in restaurant. ●79. |
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80. |
Giving cards and gifts to parents. |