英语四级终考前极仿真模拟卷(D,速读)

Part II Reading Comprehension (Skimming and Scanning)(15 minutes)

Animals on the Move
It looked like a scene from “Jaws” but without the dramatic music. A huge shark was lowly swimming through the water, its tail swinging back and forth like the pendulum of a clock。

Suddenly sensitive nerve ending in the shark’s skin picked up vibrations of a struggling fish. The shark was immediately transformed into a deadly, efficient machine of death. With muscles taut, the shark knifed through the water at a rapid speed. In a flash the shark caught its victim, a large fish, in its powerful jaws. Then, jerking its head back and forth, the shark tore huge chunks of flesh from its victim and swallowed them. Soon the action was over。

Moving to Survive
In pursuing its prey, the shark demonstrated in a dramatic way the important role of movement, or locomotion, in animals。

Like the shark, most animals use movement to find food. They also use locomotion to escape enemies, find a mate, and explore new territories. The methods of locomotion include crawling, hopping, slithering, flying, swimming, or walking。

Humans have the added advantage of using their various inventions to move about in just about any kind of environment. Automobiles, rockets, and submarines transport humans from deep oceans to as far away as the moon. However, for other animals movement came about naturally through millions of years of evolution. One of the most successful examples of animal locomotion is that of the shark. Its ability to quickly zero in on its prey has always impressed scientists. But it took a detailed study by Duke University marine biologists S. A. Wainwright, F. Vosburgh, and J. H. Hebrank to find out how the sharks did it. In their study the scientists observed sharks swimming in a tank at Marine land in Saint Augustine, Fla. Movies were taken of the sharks’ movements and analyzed. Studies were also made of shark skin and muscle。


Skin Is the Key
The biologists discovered that the skin of the shark is the key to the animal’s high efficiency in swimming through the water. The skin contains many fibers that crisscross like the inside of a belted radial tire. The fibers are called wyzfox.com. These fibers can either store or release large amounts of energy depending on whether the fibers are relaxed or taut. When the fibers are stretched, energy is stored in them the way energy is stored in the string of a bow when pulled tight. When the energy is released, the fibers become relaxed。

The Duke University biologists have found that the greatest stretching occurs where the shark bends its body while swimming. During the body’s back and forth motion, fibers along the outside part of the bending body stretch greatly. Much potential energy is stored in the fibers. This energy is released when the shark’s body snaps back the other way。

As energy is alternately stored and released on both sides of the animal’s body, the tail whips strongly back and forth. This whip-like action propels the animal through the water like a living bullet。

Source of Energy
What causes the fibers to store so much energy? In finding the answer the Duke University scientists learned that the shark’s similarity to a belted radial tire doesn’t stop with the skin. Just as a radial tire is inflated by pressure, so, too, is the area just under the shark’s collagen “radials”. Instead of air pressure, however, the pressure in the shark may be due to the force of the blood pressing on the wyzfox.com

When the shark swims slowly, the pressure on the fibers is relatively low. The fibers are more relaxed, and the shark is able to bend its body at sharp angles. The animal swims this way when looking around for food or just swimming. However, when the shark detects an important food source, some fantastic involuntary changes take place。

The pressure inside the animal may increase by 10 times. This pressure change greatly stretches the fibers, enabling much energy to be stored。
This energy is then transferred to the tail, and the shark is off. The rest of the story is predictable。

Dolphin Has Speed Record
Another fast marine animal is the dolphin. This seagoing mammal has been clocked at speeds of 32 kilometers (20 miles) an hour. Biologists studying the dolphin have discovered that, like the shark, the animal’s efficient locomotion can be traced to its skin. A dolphin’s skin is made up in such a way that it offers very little resistance to the water flowing over it. Normally when a fish or other object moves slowly through the water, the water flows smoothly past the body. This smooth flow is known as laminar flow. However, at faster speeds the water becomes more turbulent along the moving fish. This turbulence muses friction and slows the fish down。

In a dolphin the skin is so flexible that it bends and yields to the waviness of the water。

The waves, in effect, become tucked into the skin’s folds. This allows the rest of the water to move smoothly by in a laminar flow. Where other animals would be slowed by turbulent water at rapid speeds, the dolphin can race through the water at record breaking speeds。

Other Animals Less Efficient
Not all animals move as efficiently as sharks and dolphins. Perhaps the greatest loser in locomotion efficiency is the slug. The slug, which looks like a snail without a shell, lays down a slimy trail over which it crawls. It uses so much energy producing the slimy mucus and crawling over it that a mouse traveling the same distance uses only one twelfth as much energy。

Scientists say that because of the slug’s inefficient use of energy, its lifestyle must be restricted. That is, the animals are forced to confine themselves to small areas for obtaining food and finding proper living conditions. Have humans ever been faced with this kind of problem?

1.According to the passage, a shark can use movement to do something except______________。
[A]to find food
[B]to avoid being chased by its enemies
[C]to find a new place to live
[D]to show its braveness

2.Examples of automobiles, rockets and submarines are used to show that _______________。
[A]humans are the most clever living creatures in the world
[B]human inventions wyzfox.com travel in almost any kind of environment
[C]humans are very successful in inventing transportation tools
[D]humans can’t move like other animals in any circumstances

3.What is the key to the shark’s swift locomotion in water?
[A]The skin.[B]The tail.[C]The muscle.[D]The jaw。

4.According to the Duke University scientists, when does the shark stretch its wyzfox.com to the greatest extent?
[A]When moving its tail rapidly。
[B]When finding its preys。
[C]When staying without any movement。
[D]When bending its body in swimming。

5.Why is the area just under the shark’s wyzfox.com similar to a belted radial tire?
[A]Because it is also full of blood pressure。
[B]Because it is also filled of air pressure。
[C]Because it is also inflated by pressure。
[D]Because it also can be used again and again。

6.A laminar flow is formed when a fish swims________________。
[A]slowly through the water[B]rapidly through the water
[C]against the current[D]at the fastest speed in water

7.Consuming the wyzfox.com of energy as a slug does, a mouse can travelas long as it______________。
[A]one twelfth times.[B]the same.[C]12 times.[D]1.2 times。

8.A shark finds its prey by________________。
9.According to the passage, _______________can be compared to the string of a bow for both of them store energy when stretched。
10.When the shark detects an important food source, __________________________take place。

Part II Reading Comprehension (Skimming and Scanning)

【全文翻译】

动物的运动
除了缺少剧情音乐之外,这看上去就像《大白鲨》影片中的一个场景:一条巨大的鲨鱼在水中慢慢地游着,尾巴就像时钟的钟摆一样来回地摆动。
突然,它敏感的皮肤神经末梢感受到了猎物游动时发出的震动。瞬间,它就变成一台高效致命的死亡机器。它绷紧肌肉,快速地在水中砍出一条通道。眨眼之间,它便用强有力的嘴巴咬住了它的猎物,一条大鱼。随后,它来回扭动着头,从猎物的身上撕下大块大块的肉,把它们吞了下去。很快地,猎食活动就结束了。

为了生存而移动
鲨鱼追逐猎物的过程以一种夸张的方式证明了移动(或者运动)对于动物的重要作用。
像鲨鱼一样,大部分的动物通过移动来发现食物。他们还利用移动来逃避敌人、寻找配偶、开拓新的 地盘。移动的方法包括:爬行、跳跃、滑行、飞行、飘浮或者漫步。
借助各种有助移动的发明,人类加强了其移动优势,可以再任何环境下移动。汽车、火箭、潜艇能把人类从深海运输到遥远的月亮。然而,对于其他的动物而言,移动来源于数百万年的进化。鲨鱼是其中最成功的例子。它能够以接近零的时间快速地捕获猎物,这给科学家们留下了深刻的印象。但是,经过仔细的研究,美国杜克大学的海洋生物学家S. A. Wainwright、F. Vosburgh和J. H. Hebrank才发现了鲨鱼是如何做到这一点的。在研究中,科学家们对位于佛罗里达州圣奥古斯丁海上乐园泳池中游泳的鲨鱼进行了观察。他们拍摄了鲨鱼的运动情况,对它们进行了分析,同时也对鲨鱼的皮肤和肌肉进行了研究。

皮肤是关键
生物学家们发现,鲨鱼的皮肤是使它们在水中高效游泳的关键。鲨鱼的皮肤中含有许多纤维,像子午线轮胎的内部一样交错在一起。这些纤维被称为胶原纤维。随着它们的放松或拉紧,这些纤维可以储存或释放大量的能量。当拉伸纤维时,纤维中蓄满了能量,就像绷紧的弓弦一样。能量被释放后,纤维就松弛了。
杜克大学的生物学家发现,最大拉伸发生在鲨鱼弯曲身体游泳的时候。当身体前后移动时,弯曲处外侧的纤维受到强烈的拉伸,大量的潜能被储存在纤维中。当鲨鱼朝另一个方向迅速掉头时,这种能量就被释放出来了。
随着能量在鲨鱼身体两侧交替地储存和释放,它的尾巴就像鞭子一样强烈地来回摆动。这种像皮鞭一样的动作促使鲨鱼像发射的子弹一样在水中穿来穿去。

能量的来源
是什么让纤维能存储如此多的能量呢在追寻答案的过程中,杜克大学的科学家们发现,鲨鱼与子午线轮胎的相似性并不仅仅存在于皮肤上。正如子午线轮胎是由压力膨胀的一样,在鲨鱼胶原辐射处的下方也有一个膨胀区。但是,鲨鱼体内的压力可能来自于血液压缩胶原纤维而产生的压力,而不是来自于空气的压力。
当鲨鱼缓慢游动时,纤维内的压力相对较低。wyzfox.com,鲨鱼就能以锐角的角度弯身。在寻找食物或只是游动时,鲨鱼以这种方式进行移动。但是,当它发现重要的食物来源时,一些奇妙的变化就自动发生了。
鲨鱼内部的压力可能会增加10倍,胶原纤维在这种压力下剧烈拉伸,蓄积了大量的能量。
接着,这种能量被转移到尾巴上,鲨鱼快速运动起来,剩下的事情就可想而知了。

海豚是速度最快的纪录保持者
海豚是另一种快速的海洋动物,这种海洋哺乳动物的速度为每小时20英里。研究海豚的生物学家们发现,就像鲨鱼一样,海豚的快速游动可以追溯到其皮肤。海豚的皮肤是这样构成的:它对流过其身体的水流产生的阻力很小。通常情况下,当鱼或其他动物在水中缓慢游动时,水流会平稳地流过wyzfox.com种平稳的水流被称为层流。然而,当鱼快速移动时,其周围的水流就变得湍急起来。这种乱流使摩擦加大,降低了鱼的速度。
海豚的皮肤弹性很大,可以随着水波的波形而弯曲。实际上,水波是被卷进了海豚皮肤的皱褶处。这样,其余的水就以层流的方式从其身边平稳地流过。其他动物快速游动时,由于受到乱流的阻碍,其速度就降低了;但是,海豚却能够以破纪录的速度在水中快速穿行。

其他的低速动物
并不是所有的动物都能像鲨鱼和海豚一样快速地游动。在运动效率方面最大的输家可能是蛞蝓(鼻涕虫)。它看起来就像没有壳的蜗牛,wyzfox.com会留下一条细细的踪迹。它要使用大量的能量制造粘滑的粘液,以便在其上爬行。移动同样的的距离,老鼠只需要其所耗费能量的十二分之一。
科学家们认为,由于蛞蝓(鼻涕虫)利用能量的效率很低,所以它的生活必然受到一定的限制。换句话说,它们都被迫把自己束缚在很小的区域之中来搜寻食物和寻找合适的生活条件。人类曾经面临过这样的问题吗

【答案解析】
1.【解析】[D]属同义转换题,本题是一种排除选择题。根据题干中的中心词“movement to do something”,可以将答案定位在小标题“Moving to Survive”下第二段的前两句话,“Like the shark, most animals use movement to find food. They also use locomotion to escape enemies, find a mate, and explore now territories”。该句与题干是一种同义转换,选项A、B和C在原文中均有提及,所以不是正确选项;答案D在原文没有提及,所以是正确答案。
2.【解析】[B]属细节推断题。题干考查汽车、火箭和潜艇的例子是为了说明什么,其中的“examples of automobiles, rockets and submarines”是关键词,可以将答案定位在文章小标题“Moving to Survive”下第三段的前两句话,“Humans have the added advantage of using their various inventions to move about in just about any kind of environment. Automobiles, rockets, and submarines transport humans from deep oceans to as far away as the moon”,第二句话所举例子正是为了说明第一句话的内容,这与B项意思一致,而其它选项在文中均未提及。
3.【解析】[A]属细节推断题。分析题干,本题考查鲨鱼在水中快速游动的关键是在什么。其中的“key”是关键词,可以将答案定位在小标题“Skin Is the Key”下首段的第一句话,“The biologists discovered that the skin of the shark is the key to the animal’s high efficiency in swimming through the water”,这与选项A完全一致,所以直接选择A即可。其它选项在文中均有提及,但是都不符合题干的要求。
4.【解析】[D]属细节推断题。题干中的“the Duke University scientists”是关键词,可以将答案定位在小标题“Skin Is the Key”下第二段的第一句话,“The Duke University biologists have found that the greatest stretching occurs where the shark bends its body while swimming”。这与选项D的内容完全一致,所以答案选D项,而其它选项原文均为提及,为干扰项。
5.【解析】[C]属细节推断题。题干中“a belted radial tire”是关键词,可以将答案锁定在文章小标题“Source of Energy”下第一段的第三句话,“Just as a radial tire is inflated by pressure, so, too, is the area just under the shark’s collagen ‘radials’”。其中的“just as”和“so”正说明了两者的相似之处在于“inflated by pressure”,所以答案应该是C。选项A和B是两者的不同之处,选项D在文中没有提及。
6.【解析】[A]属细节推断题。题干中的关键词是“a laminar flow”,所以可以将答案锁定在文章小标题“Dolphin Has Speed Record”下,根据该节第一段的倒数第三、四句话,“Normally when a fish or other object moves slowly through the water, the water flows smoothly past the body. This smooth flow is known as laminar flow。”。题干是对这两句话的改写,所以正确答案是A选项。其它三个选项的意思均不符合“a laminar flow”的定义,与题干要求不符。
7.【解析】[C]属同义转换题。题干中“a slug”和“a mouse”均为关键词,可以直接定位在小标题“Other Animals Less Efficient”下第一段的第二句话,“It uses so much energy ... a mouse traveling the same distance uses only one twelfth as much energy”。题干是对该句的同义改写,所以正确答案是C 12 times,其它选项均与原文内容不符。
8. 【解析】feeling the vibrations of a struggling prey鲨鱼靠感受猎物游动的震动来发现猎物。
9. 【解析】wyzfox.com 在Skin Is the Key中,第二、三句话,The fibers are called wyzfox.com
10. 【解析】some fantastic involuntary changes 在Source of Energy中,第二段倒数第一句话就是本题答案。

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