题目内容

Some researchers believe that there is no doubt ______ a cure for AIDS will be found.

  A. which     B. that         C. what          D. whether 

B


解析:

主要测试同位语从句。结合平时的学习可知单词doubt后面的引导词:肯定句中用

whether或if;否定句中用that。因此答案已经明了。意思:一些研究人员相信治疗艾滋病的方法一定会找到的。例如:I have no doubt that he will come。我相信他会来的。

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Sheep, like turkeys and ostriches, are not considered the cleverest animals. British scientists said last Wednesday human may have underestimated(低估) the woolly creatures. They could be much smarter than we think.

Researchers at the Babraham Institute in Cambridge, southern. England, have shown that animals have a good memory system and are extremely good at recognizing faces--which they think is a sure sign of intelligence.

Behavioral scientist Keith Kendrick and his friends trained 20 sheep to recognize and distinguish(区别) 25 pairs of sheep faces and used electrodes(电极) to measure their brain activity, which showed they could remember 50 faces for up to two years.

"If they can do that with faces, the fact is that they have to have reasonable intelligence, otherwise, what is the point of having a system for remembering anything else," Kendrick said in an interview.

So hours of seemingly mindless eating grass may not be so mindless after all.

Kendrick believes sheep got their reputation as dumb animals because they live in large groups and do not appear to have much ind

ividuality and are frightened of just about everything.

All animals, including humans, once they are frightened don't tend to show signs of intelligent action," he explained.

In research reported in the science journal Nature, Kendrick and his team showed that sheep, like humans, have a specialized system in the brain, which allows them to distinguish between many different faces that look extremely similar.

"The most important findings of the study is that they are able, both from a behavioral point of view and from looking at the way the brain is organized, to remember a large number of faces of individuals for a very long time," said Kendrick. "It is a very strange system. They are showing similar abilities in many ways to humans. "

From the first paragraph we can find that ______.

   A. people used to think sheep are smarter than the other animals

   B. people used to raise sheep in a wrong way

   C. people don't consider sheep as clever animals

   D. people have done a lot of research on sheep

From what Kendrick said in the interview we learn that ________.

   A. scientists have learned a lot about sheep's intelligence

   B. scientists have learned little about sheep's intelligence

   C. scientists can't do anything more about sheep's memory

   D. scientists don't have to research animals' memory

As is shown in the passage _________.

   A. sheep are among the weak animals

   B. it is not right for people to raise sheep in groups

   C. when sheep eat grass in the fields their minds may be active

   D. if people feel frightened, they may become more brave

When scientists found that sheep show similar abilities in many ways to humans they may think it _____.

   A. worrying          B. moving           C. frightening           D. interesting

Among the dead in South Asia’s tsunami were many tourists at Sri Lanka’s national wildlife park at Yala. But very few of the park’s animals — elephants, buffaloes, monkeys and wild cats — appear to have died. There are theories that animals can sense natural disasters and flee to safety.

First, it’s possible that the animals may have heard the quake before the tsunami hit. The underwater rupture likely produced sound waves known as infrasound or infrasonic sound. Humans can’t hear infrasound, but many animals including dogs, elephants, tigers and pigeons can.

A second early warning sign the animals might have sensed is ground vibration. The massive quake would have produced vibrational waves known as Rayleigh waves. These vibrations move through the ground like waves move on the surface of the ocean but faster. They travel at ten times the speed of sound. The Rayleigh waves would have reached SriLanka hours before the water hit. Mammals, birds, insects and spiders can sense Rayleigh waves. So the animals at Yale might have felt the Rayleigh waves and then run to higher ground.

But what about humans? While we can’t hear infrasound, we can feel it, although we don’t necessarily know we’re feeling it. We also experience Rayleigh waves by special sensors in our joints, which exist just for that purpose. Sadly, it seems we don’t pay attention to the information when we get it. Maybe we screen it out because there’s so much going on before our eyes and in our ears. Humans have a lot of things on our minds and usually that works out OK.

Notes:

tsunami  n. 海啸

infrasound  n. 次声

vibration  n. 振动,颤动

Choose the best answers according to the above:

Why did few animals at Yala die when the tsunamis that caused a huge number of human deaths hit?

A. Because the animals were staying at a higher place in the park.

B. Because the animals were able to run much faster than human beings.

C. Because human beings cannot hear the infrasonic sound.

D. Because the animals might have picked up the danger signals and ran away.

Which of the statements about “Ravleigh waves” is true?

A. Rayleigh waves are massive vibrational waves that usually cause quakes or tsunamis.

B. Rayleigh waves move on the ocean surface at a speed ten times that of sound waves.

C. Rayleigh waves can be felt both by animals and human beings.

D. Rayleigh waves, just like infrasonic sound, can only be felt by animals.

When a tsunami hits, it is possible that ____.

A. we can’t feel the infrasound so we can’t be informed of the danger

B. we can feel Rayleigh waves as well as infrasound so we are able to escape the danger like animals

C. we were so busy with things on our minds that we feel neither infrasound nor Rayleigh waves

      D. we think nothing of the information of its coming even though we can also get it

What does the underlined word “that” in the last sentence refer to?

A. Screening out the information.

B. There being so much going on before our eyes and in our ears.

C. Having a lot of things on our minds.

D. Paying attention to the information.

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