职称英语考试

试题来源：2015年职称英语《理工类》热身模拟试题及答案(2)
【单选题】　　The Exploding Lakes of Cameroon
    What comes to mind when you think of a lake? You probably imagine a pretty scene withblue water, birds, and fish. For the people in the northwestern Cameroon, however, the image is very different. For them, lakes may mean terrible disasters. In 1984, poisonous gasesexploded out of Lake Monoun and came down into the nearby villages, killing thirty-sevenpeople. Two years later, Lake Nyos erupted. A cloud of gases rolled down the hills and into thevalleys and killed 1,700 people.
     Lake Nyos and Lake Monoun are crater (火山口) lakes They were formed when watercollected in the craters of old volcanoes. The volcanoes under Lake Nyos and Lake Monoun arenot active anymore. However, poisonous gases from the center of the earth continue to flow upthrough cracks in the bottom of the lake. This is normal in a crater lake. In most crater lakes,these gases are released often because the water "turns over" regularly. That is, the water fromthe bottom of the lake rises and mixes with the water at the top, allowing the gases to escapeslowly.
    However, in Lakes Nyos and Monoun, there is no regular turning over. No one knows thereason for this fact, but as a result, these lakes have more gases tapped at the bottom than othercrater lakes. In fact, scientists who have studied Lakes Nyos and Monoun have found 16,000times more gases. When a strong winD. cool weather a storm, or a landslide (滑坡) causesthe water to turn over suddenly, the gases escape in a violent explosion.
    In the past, no one knew when the gases might explode, so there was no way for thevillagers to escape disaster. Now scientists from the United States, France, and Cameroon havefound a way to reduce the gas pressure at the bottom of Lake Nyos. They stood a 672-footplastic pipe in the middle of the lake, with one end of the pipe near the bottom and the otherend in the air. Near the top of the pipe, the team putseveral holes that could be opened orclosed by a computer. Now, when the gas pressure gets too high, the holes are opened andsome of the gas-filled water shoots up through the pipe into the air like a fountain. With lesspressure, a disastrous explosion is much less likely. However, the scientists are not sure thatone pipe will be enough to prevent explosions. They hope to put in others soon and they plan toinstall a similar pipe and a computer system at Lake Monoun as well.
    To protect people nearby until all of the pipes are in place, the scientists have installedearly warning systems at both lakes. If the gas pressure rises to a dangerous level, computerswill set off loud sirens (劲爆) and bright lights to warn the people in the villages. That way,they will have time to escape from the dangerous gases.
41、What will happen when Lake Nyos and Lake Monoun explode_________?
A.Water will flow down the hills
B.Poisonous gases will be released suddenly.
C.A strong wind will rise from the lakes
D.The volcanoes will come to life.
42、 Which of the following statements about Lake Nyos and Lake Monoun is true_________?
A.They were formed in 1984.
B.They are at the top of two active volcanoes.
C.They are not like most other crater lakes.
D.Water in them turns over regularly.
43、 Lake Nyos and Lake Monoun explode because_________
A.the gases rise to the top and mix with air
B.people from the villages turn over the water
C.scientists have put in a computer system
D.they have more gases trapped at the bottom than other Crater lakes
44、 A team of scientists has_________
A.erected a pressure-releasing pipe in the lake
B.identified the gases at the bottom of the lake
C.built a beautiful fountain near the lakes
D.removed all dangerous gases from the lakes
45、What do we learn from the last paragraph_________?
A.Scientists are planning to install pipes in all crater lakes.
B.Scientists still do not know how to prevent gas explosions.
C.Explosion disasters could be avoided in the future.
D.Warning systems have been set up in the villages nearby.

试题出处：http://www.examtiku.com/shiti/7167126722.html
网考网参考答案：B、C、D、B、C
网考网解析：进入考试题库查看解析
大数据分析：根据网考网与考试题库的统计分析，该试题：
27%的考友选择了A选项
18%的考友选择了B选项
17%的考友选择了C选项
38%的考友选择了D选项
考友解析与评论：
 · 我觉得B、C、D、B、C也不对
 · 我也是这么错的
 · 像这种考试，没什么技术含量，全靠运气。