题目
题型：不详难度：来源：
In an effort to improve the situation, the U.S. government has made regulations on the use of the constituents (成分) of automobile exhaust gas that are known to cause air pollution. These constituents fall roughly into three types: hydrocarbons that pass through the engine unburned; carbon monoxide, also a product of incomplete burning; and nitrogen oxides which are formed when nitrogen and oxygen are in contact at high temperatures. Besides their own poisonous character, hydrocarbons and nitrogen oxides react in the presence of sunlight to form harmful smog. Carbon monoxide and hydrocarbons are rather easily controlled by the use of higher burning temperatures in engines. Unfortunately, the conditions that produce minimum emission of hydrocarbons tend to raise emission of nitrogen oxides. In a way this difficulty is solved by adding recycled exhaust gas to the fuel mixture, thus avoiding the oversupply of oxygen that favors formation of nitrogen oxides.
California, which has the most strict air-pollution laws in the United States, requires further special compounding of gas to control emissions, and several states have ordered that alcohol be mixed with gas, as this will reduce emissions of the carbon monoxide by 35 per cent and the hydrocarbons by 15 per cent.
小题1:The author uses figures in Paragraph 1 ________.
| A．to reflect the rapid growth of automobile use |
| B．to highlight the importance of environment protection |
| C．to show the consequence of automobile exhausts |
| D．to criticize the low quality of cars |
| A．Nitrogen and oxygen are put together in great heat. |
| B．Carbon monoxide and oxygen are mixed together. |
| C．Hydrocarbons pass through the engine. |
| D．Nitrogen is burned incompletely. |
| A．Carbon monoxide can be controlled in the engine. |
| B．Smog will form when hydrocarbons meet nitrogen oxides in the sunlight. |
| C．Hydrocarbons have no poisonous character themselves. |
| D．The conditions that decease emission of hydrocarbons will increase emission of nitrogen oxides. |
| A．increase awareness of environment protection |
| B．control air pollution |
| C．increase the fuel efficiency |
| D．replace gas gradually |
答案
小题1:C
小题2:A
小题3:C
小题4:B
解析
试题分析：文章介绍现在因为汽车尾气的排放，空气受到严重的污染，文章分析汽车尾气的成分和它们的危害，同时介绍解决空气污染问题的方法。
小题1:细节题：从第一段的句子：that 70% of the carbon monoxide(一氧化碳), 45% of the nitrogen oxides(氮氧化合物), and 34% of the hydrocarbon (碳氢化合物) pollution in the United States can be traced directly to automobile exhausts (废气). 可知这些数字表明汽车废气的后果，选C
小题2:细节题：从第二段的句子：nitrogen oxides which are formed when nitrogen and oxygen are in contact at high temperatures.可知 氮氧化合物和碳氢化合物是通过热量结合的，选A
小题3:细节题：从第二段的句子：Besides their own poisonous character, hydrocarbons and nitrogen oxides react in the presence of sunlight to form harmful smog. 可知碳氢化合物本身也是有毒的，选C
小题4:细节题：从最后一段的句子：states have ordered that alcohol be mixed with gas, as this will reduce emissions of the carbon monoxide by 35 per cent and the hydrocarbons by 15 per cent. 可知把酒精加入到汽油里面，是为了减少空气污染。选B
核心考点
试题【Pollutants coming from automobile operation have begun to cause many environment】；主要考察你对题材分类等知识点的理解。[详细]
举一反三
Size: 4,028 square miles.
Population: 148,677. The most heavily populated areas are Hilo on the east side and Kailua-Kona on the west.
Temperature: Averages between 71℉ and 77 ℉ year around —expect the mercury ( 水银柱) to drop at higher Heights.
Beaches: 47 Golf Courts: 20 Highest Peak: Mauna Kea, 13,796 feet.
Agriculture: The bulk (主体) of Hawaii’s farming products are grown and processed on the Big
Island, including coffee, macadamia nuts and papaya.
Lodging: 9,655 rooms in total; nightly rates range from $ 35 to $ 5,000.
Airports: Hilo International Airport on the east side and Kona International Airport on the west
side.
Rental Cars: All of the nationally known rental car companies have locations at Hilo International and Kona International Airports as well as many resorts. In addition, Hilo, Kona and the major resort areas are serviced by taxis.
Resources: Call (800) 648-2441 to order a video, a poster, brochures and maps from the Big Island Visitors Bureau. Turn to www. Bigisland. org for updated information.
Shopping: The largest shopping centers are in Hilo, Kona, Waimea and the Kona Coast.
小题1:_____ are mostly interested in reading the passage.
| A．Tourists | B．Students | C．Businessmen | D．Officials |
| A．28 | B．37 | C．32 | D．44 |
| A．Things are easy to lose weight at higher places |
| B．Dropping things from higher places is expected |
| C．Temperature is expected to be lower at higher places |
| D．Temperature is expected to be higher at higher places |
Water shortage , already serious in Egypt and Sudan , will soon influence several other countries in the watershed as well．Today, about 160 million people depend on the Nile River for their living．Within the next 25 yeas ,the district"s population is expected to double, adding to the demand brought about by growth in industry and agriculture．The frequent drought（干旱）adds to the urgency.
Water quality is also a problem．Precious soil is washed out to sea．Wastes from industry and agriculture create pollution．Higher concentrations of salt influence irrigated soils．Water-borne diseases continue unchecked．In areas where it"s hot and damp, water hyacinths choke off（阻止） lakes, dams and other sections of the river, making it difficult for fishing and other businesses to move forward.
Native people along the narrow area of farmland have watched the sand move closer day by day．They’ve seen the river change course, and their only source（来源） of water thickened with mud．They’re very poor and have few choices.
But a new program, the Nile Basin Initiative (NBI), is offering very practical assistance．The program is more than just a water-management project．It’s a plan for the social and economic development of a vast district: it concentrates on the needs of the poorest of the poor and the environment that supports them.
These are whole ecosystem problems, calling for united solutions．Half the Nile Basin"s countries are among the world"s poorest nations；yet, somehow, they must find the resources, skills and political will to overcome these challenges.
小题1:What are the great challenges the Nile Basin faces？
| A．The development of shipping industry. |
| B．Over fishing of native people. |
| C．Water shortage and water quality. |
| D．Increasing population and tourism. |
| A．plants | B．animals | C．rocks | D．salts |
| A．preventing water pollution |
| B．improving living condition of the poor |
| C．changing the river course |
| D．preventing land from becoming desert |
| A．People’s Life in Egypt and Sudan |
| B．Frequent Drought in Egypt and Sudan |
| C．The Poorest Countries in the Nile Basin |
| D．The Ecosystem Problems in the Nile Basin |
“Global warming is having a great effect on hundreds of plant and animal species around the world, changing some living patterns.” scientists say.
Increased carbon dioxide (CO2) in the air from burning coal and oil can have an effect on how plants produce oxygen, while higher temperatures and changeable rainfall patterns can change their patterns of growth.
“Predicting species’ reaction to climate change is a major challenge in ecology,” said the researchers of several U.S. Universities. They said plants had been the key object of study because their reaction to climate change could have an effect on food chains and ecosystem services.
The study, published on the Nature website, uses the findings from plant life cycle studies and experiments across four continents and 1,634 species. It found that some experiments had underestimated the speed of flowering by 8.5 times and leafing by 4 times.
“Across all species, the experiments underestimated the speed of the advance—for both leafing and flowering—that results from temperature increases,” the study said.
“The design of future experiments may need to be improved to better predict how plants will react to climate change,” it said.
Plants are necessary for life on the Earth. They are the base of the food chain, using photosynthesis (光合作用) to produce sugar from carbon dioxide and water. They let out oxygen which is needed by nearly every organism on the planet.
Scientists believe the world’s average temperature has risen by about 0.8 ℃ since 1900, and nearly 0.2 ℃ every ten years since 1979.
So far, efforts to cut emissions of planet-warming greenhouse gases are not seen as enough to prevent the Earth heating up beyond 2 ℃ this century—a point scientists say will bring the danger of a changeable climate in which weather extremes are common, leading to drought, floods, crop failures and rising sea levels.
小题1:What is the key information the author wants to give in Paragraph 1?
| A．The increasing speed of flowering is beyond scientists’ expectation. |
| B．Climate change leads to the change of food production patterns. |
| C．Plants’ reaction to weather could have damaging effects on ecosystem. |
| D．Food chains have been seriously damaged because of weather. |
| A．scientists should improve the design of the experiments |
| B．plants’ flowering is 8.5 times faster than leafing |
| C．there are 1,634 plant species on the four continents |
| D．the experiments failed to predict how plants react to climate change |
| A．they can prove the climate change clearly |
| B．they are very important in the food chains |
| C．they play a leading role in reducing global warming |
| D．they are growing and flowering much faster than before |
| A．It has risen nearly 0.2 ℃ since 1979. |
| B．It is 0.8 ℃ higher in 1979 than that of 1990. |
| C．It needs to be controlled within 2 ℃ in this century. |
| D．Its change will lead to weather extremes. |
Many people like to watch others play games. They buy tickets or turn on their TVs to watch the games. Often they get very excited when “their” player or team wins.
Some sports are so interesting that people everywhere go in for(参加) them. Football, for example, has spread(展开)around the world. Swimming is popular in all countries near the sea or in those with many rivers. What fun it is to jump into a pool or lake, whether in China, Egypt or Italy! And think of people in cold countries. Think how many love to skate or ski (滑雪) in Japan, Norway or Canada.
Some sports or games go back thousands of years, like running or jumping. Chinese wushu, for example, has a very long history. But basketball and volleyball are rather new. Neither one is a hundred years old yet. People are inventing new sports or games all the time. Water-skiing is one of the newest in the family of sports.
People from different countries may not be able to understand each other, but after a game together they often become good friends. Sports help to train a person’s character. One learns to fight hard but fight fair, to win without pride and to lose with grace(胜不骄，败不馁).
小题1:Why do people all over the world enjoy sports?
| A．Because they are healthy. |
| B．Because they are happy. |
| C．Because they want to live longer. |
| D．All the above. |
| A．their favourite team wins | B．they win the game |
| C．they get the good news | D．they can’t help themselves |
| A．they train their character in the game |
| B．they understand each other |
| C．they are friendly to each other |
| D．they help each other |
The Lewisvillle, Texas, school teachers were aware that the hours they spent on preparing lessons were too often wasted on many students. So Forestwood High School, Texas, used the “flipped (翻转的) classroom” method of instruction. “We’ve completely done away with our lecture,” Derow said. And homework assignments “are all done in class,” Bradley said.
With the flipped concept, a student’s usual homework assignment is to watch pre-recorded lectures on their computers or smart phones.They walk into class ready to discuss the topic, collaborate(合作) with other students and work on assignments based on what they learned from the video. Free from lecturing, the teachers can use class time to look deeper into the subject and focus on difficult concept. As students change from a passive to an active role, they learn critical thinking skills, learn to collaborate and become independent learners.
Instead of doing homework assignments alone at home, students are now “working together, talking about it,” Bradley said. “If they don’t agree on an answer, they debate it and have to justify their answers. It’s a higher level of learning.”
Her students give the flipped classroom high marks.
Sarah Lee, 14, watches the 30-minute videos on a home computer. She likes the ability to rewind the tapes if she doesn"t understand a concept. She also likes being able to watch the lessons on her own schedule.
One of her classmates, Dawson Depperschmidt has the same idea and thinks the time she spends in the classroom is more productive. “It gives us more time to learn at school,” Dawson said. “You get more in-depth in class.
小题1:What can we conclude from the first two paragraphs?
| A．Teachers in Lewisville enjoyed giving classroom lectures. |
| B．It takes time for students to concentrate and understand in class. |
| C．Many students took an inactive part in lecture-style classes. |
| D．Teachers in Lewisville found that there was no need to prepare lessons. |
| A．They have more arguments with classmates. |
| B．They have to be independent and cooperative. |
| C．They need to do more homework at home. |
| D．They have to prepare lectures by themselves. |
| A．reducing difficulties | B．trying new methods |
| C．achieving a lot | D．causing troubles |
a. Teachers have time to solve deeper problems
b. Students are engaged in a higher level of learning.
c. Students study according to their own schedule.
d. Teachers don’t have to design homework for students
| A．a, b, c, | B．a, c, d | C．b, c, d | D．a, b, d |
最新试题
- 1如图为撑杆跳运动员在比赛中的几个画面，下列说法中正确的是（ ）A．运动员过最高点时的速度为零B．运动员过最高点时的加速
- 2若x+2+|y-1|=0，则x2-y2=______．
- 3下列说法正确的是A．温度升高，物体的每一个分子的动能都增大B．气体的压强是由气体分子间的吸引和排斥产生的C．当两个分子间
- 412g镁与足量稀硫酸反应，生成氢气多少克？（反应的化学方程式为：Mg + H2SO4===MgSO4 + H2↑）
- 5的值为 .
- 6下列常见合成材料中，不是由加聚反应制得的是（ ）A．聚苯乙烯：B．有机玻璃：C．聚丙烯：D．涤纶：
- 7已知椭圆中心在原点，一个焦点为（3，0），且长轴长是短轴长的2倍，则该椭圆的标准方程是______．
- 8如图所示的装置，物块M放在粗糙程度相同的水平桌面上，左右两端用细线通过滑轮连接着两个相同的吊盘。小聪用它做实验时发现：当
- 9Your mother looks a bit disappointed. You ______ have told h
- 10下列图示能够准确全面表述各事件之间相互关系的是：
热门考点
- 1解下列方程组：（1）（2）
- 2——I haven"t got a camera.——I think you should buy_______. It
- 3下列化合物可由两种单质直接化合得到的是A．NO2B．SO2C．CuSD．FeCl2
- 4下列式子中，不成立的是（ ）A．（x-y+z）（x-y-z）=（x-y）2-z2B．（x+y-z）（x-y-z）=x2
- 5《近代中国的新陈代谢》中写道：“这场战争，自西方人1514年到中国起，是他们积325年窥探之后的一逞。对于中国人来说，这
- 6等轴双曲线的一个焦点是，则它的标准方程是（ ）A．B．C．D．
- 7A、B两个城市的位置如图所示，那么B城在A城的______方向．
- 8给女儿的一封信 刘墉今天我看美国网球公开赛的时候，你过来瞄了几眼，说：“奇怪，这个达文波特为什么没表情?她赢球没露出
- 9质点做直线运动的v一t图象如图所示，规定向右为正方向，则该质点在前8s内平均速度的大小和方向分别为[ ]A．0.
- 10人在运动时的心跳速率通常和人的年龄有关．如果用a表示一个人的年龄，用b表示正常情况下这个人在运动时所能承受的每分钟心跳的