测器) to keep it away from danger. It is powered entirely by the sun. Should we program the robot to
be equally active at all time? No.The robot would be using up energy at a time when it was not receiving
any. So we would probably program it to stop its activity at night and to wake up at dawn the next
morning.
According to the evolutionary (进化的) theory of sleep, evolution equipped us with a regular pattern
of sleeping and waking for the same reason.The theory doesn"t deny that
sleep provides some important restorative functions. It merely says that evolution has programmed us to
perform those functions at a time when activity would be inefficient and possibly dangerous. However,
sleep protects us only from the sort of trouble we might walk into; it doesn"t protect us from trouble that
comes looking for us. So we sleep well when we are in a familiar and safe place, but we sleep lightly, if at
all,when we fear that bears will nose into the tent.
The evolutionary theory explains the differences in sleep among creatures.Why do cats,for instance,
sleep so much,while horses sleep so little? Surely cats do not need five times as much repair and
restoration as horses do.But cats can afford to have long periods of inactivity because they spend little
time eating and unlikely to be attacked while they sleep. Horses must spend almost all their waking hours
eating, because what they eat is very low in energy value. Moreover,they cannot afford to sleep too long
or too deeply, because their survival depends on their ability to run away from attackers.
B.the reason why men need to sleep
C.about the need for robots to save energy
D.about the danger of men working at night
B. restore his bodily functions
C. prevent trouble that comes looking for him
D. keep up a regular pattern of life
B. need more time for restoration
C. spend less time eating to get enough energy
D. are unlikely to be attackers
B. The sleeping pattern of a living creature is determined by the food it eats.
C. Sleeping patterns must be taken into consideration in the designing of robots.
D. Evolution has equipped all creatures with a regular pattern of sleeping against waking.
commercial whaling and is now listed as an endangered species. Attaching radio equipment to it is
difficult and visual sightings are too unreliable to give real insight into its behavior.
So biologists were delighted early this year when with the help of the Navy they were able to track a
particular blue whale for 43 days monitoring its sounds . This was possible because of the Navy"s
formerly top-secret system of underwater listening equipment spanning (估量) the oceans . Tracking
whales is but one example of an exciting new world just opening to civilian scientists after the cold war
as the Navy starts to share and partly uncover its global network of underwater listening system built
over the decades to track the ships of potential enemies .
Earth scientists announced at a news conference recently that they had used the system for closely
monitoring a deep-sea volcanic eruption for the first time and that they plan similar studies. Other
scientists have proposed to use the network for tracking ocean currents and measuring changes in ocean
and global temperatures. The speed of sound in water is roughly one mile a second-slower than through
land but faster than through air. What is most important , different layers of ocean water can act as
channels for sounds focusing them in the same way a stethoscope (听诊器) does when it carries faint
noises from a patient"s chest to a doctor"s ear. This focusing is the main reason that even relatively weak
sounds in the ocean especially low frequency ones can often travel thousands of miles.
B. the civilian use of a military detection system
C. the exposure of a U. S. Navy top-secret weapon
D. a new way to look into the behavior of blue whales
A. to mark and locate enemy ships
B. to monitor deep-sea volcanic eruptions
C. to study the movement of ocean currents
D. to replace the global radio communications network
B. the capability of sound to travel at high speed
C. the special quality of layers of ocean water in sending out sound
D. low-frequency sounds traveling across different layers of water
B. blue whales are no longer endangered with the use of the new listening system
C. opinions differ as to whether civilian scientists should be allowed to use military technology
D. military technology has great potential in civilian use
B. It has been replaced by a more advanced system.
C. It became useless to the military after the cold war.
D. It is necessary in protecting endangered species.
blood type O, you are a leader. When you see something you want, you strive to achieve your goal. You
are passionate, loyal, and self-confident, and you are often a trendsetter. Your enthusiasm for projects
and goals spreads to others who happily follow your lead. When you want something, you may be
ruthless about getting it or blind to how your actions affect others. Another blood type, A, is a social,
"people" person. You like people and work well with them. You are sensitive, patient, compassionate,
and affectionate. You are a good peacekeeper because you want everybody to be happy. In a team
situation, you resolve conflicts and keep things on a smooth course. Sometimes type As are stubborn and
find it different to relax. They may also find it uncomfortable to do things alone.
People with type B blood are usually individualists who like to do things on their own. You may be
creative and adaptable, and you usually say exactly what you mean. Also you can adapt to situations,
you may not choose to do so because of your strong independent streak. You may prefer working on
your own to being part of a team. The final blood type is type AB. If you have AB blood, you are a
natural entertainer. You draw people to you because of your charm and easygoing nature. ABs are
usually calm and controlled, tactful and fair. On the downside, though, they may take too long to make
decisions. And they may procrastinate, putting off tasks until the last minute.
B. self-oriented
C. be considerate
D. set the fashion
B. Sensitive.
C. Reserved.
D. Patient.
B. He doesn"t think much before he speaks.
C. He has many original ideas.
D. He cannot fit in with the environment.
B. Peacekeeper
C. Actor
D. Country leader
and save the endangered species(物种). That"s a move similar to what a Texas A & M University
researchers have been undertaking for the past five years in a project called "Noah"s Ark".
Noah"s Ark is aimed at collecting eggs, embryos(胚胎), semen and DNA of endangered animals and
storing them in liquid nitrogen. If certain species should become extinct, Dr. Duane Kraemer, a professor
in Texas A & M"s College of Veterinary Medicine, says there would be enough of the basic building
blocks to reintroduce the species in the future.
It is estimated that as many as 2, 000 species of mammals, birds reptiles will become extinct in over
100 years. The panda, native only to China, is in danger of becoming extinct in the next 25 years.
This week, Chinese scientists said they grew an embryo by introducing cells from a dead female panda
into the egg cells of a Japanese white rabbit. They are now trying to implant the embryo into a host animal.
The entire procedure could take from three to five years to complete.
"The nuclear transfer(核子移植) of one species to another is not easy, and the lack of available
panda eggs could be a major problem," Kraemer believes. "They will probably have to do several
hundred transfers to result in one pregnancy (having a baby). It takes a long time and it"s difficult, but this
could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it
is worth the effort," adds Kraemer, who is one of the leaders of the Project at Texas A & M, the
first-ever attempt at cloning a dog.
"They are trying to do something that"s never been done, and this is very similar to our work in
Noah"s Ark. We"re both trying to save animals that face extinction. I certainly appreciate their effort and
there"s a lot we can learn from what they are attempting to do. It"s a research that is very much needed."
B. save endangered animals from dying out
C. collect DNA of endangered animals to study
D. transfer the nuclear of one animal to another
B. host animals
C. qualified researchers
D. enough money
B. The First Cloned Panda in the World
C. Exploring the Possibility to Clone Pandas
D. China -the Native Place of Pandas Forever
B. scientists try to implant a panda"s egg into a rabbit
C. Kraemer will work with Chinese scientists in clone researches
D. about two thousand of species will probably die out in a century
Algae(水藻) are very simple plants. They grow in fresh water or salty water. Seaweed is algae that
grow in salty water. Seaweed is red or brown in color. The Japanese people use these plants from the
sea in many ways. From it, they make a food called Kombu. Kombu is seaweed that has been dried,
cooked and pressed together. Then it is dried again and cut into long pieces. The Japanese eat a lot of
Kombu and like it very much.
Japanese farmers often use seaweed as fertilizer. It makes their plants grow better. Many farmers
also find seaweed makes a fine food for their animals.
From seaweed the Japanese also get iodine(碘), which they sell to other countries. Iodine is used
in many ways all over the world. It is used in making medicine. It is added to the salt we use at the table.
Scientists even use one form of iodine to “ seed clouds” when they want rain to fall.
B. medicine
C. food
D. fertilizer
2. In the last sentence of the text, “seed clouds” means ____.
B.the seeds like clouds
C.to make rain fall with human power
D.dropping seeds by clouds
B.Kombu is made into medicine for farmers.
C.The Japanese use seaweed in many ways.
D.The Japanese eat a lot of Kombu.
before they start speaking, and later starters are often long listeners. Most children will "obey" spoken
instructions some time before they can speak, though the word "obey" is hardly accurate as a
description of the eager and delighted cooperation usually shown by the child. Before they can speak,
many children will also ask questions by gesture and by making questioning noises. Any attempt to study
the development from the noises babies make to their first spoken words leads to considerable difficulties. It is agreed that they enjoy making noises, and that during the first few months one or two noises sort
themselves as particularly expressive as delight, pain, friendliness, and so on. But since these can"t be
said to show the baby"s intention to communicate, they can hardly be regarded as early forms of
language. It is agreed, too, that from about three months they play with sounds for enjoyment, and that
by six months they are able to add new words to their store. This self-imitation leads on to deliberate (有意的) imitation of sounds made or words spoken to them by other people. The problem then arises as to
the point at which one can say that these imitations can be considered as speech. It is a problem we need
to get out. The meaning of a word depends on what a particular person means by it in a particular
situation and it is clear that what a child means by a word will change as he gains more experience of the
world .Thus the use at seven months of "mama" as a greeting for his mother cannot be dismissed as a
meaningless sound simply because he also uses it at other times for his father, his dog, or anything else he
likes. Playful and meaningless imitation of what other people say continues after the child has begun to
speak for himself, I doubt, however, whether anything is gained when parents take advantage of this
ability in an attempt to teach new sounds.
B. they need different amounts of listening
C. they are all eager to cooperate with the adults by obeying spoken instructions
D. they can"t understand and obey the adult"s oral instructions
B. probably do not hear enough language spoken around them
C. usually pay close attention to what they hear
D. often take a long time in learning to listen properly
B. an early form of language
C. a sign that he means to tell you something
D. an imitation of the speech of adults
B. is one that should be properly understood because the meaning of words changes with age
C. is not especially important because the changeover takes place gradually
D. is one that should be completely ignored (忽略) because children"s use of words is often meaningless
B. even after they have learnt to speak, children still enjoy imitating
C. children no longer imitate people after they begin to speak
D. children who are good at imitating learn new words more quickly
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