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Batteries Built by Viruses
What do chicken pox,the common cold,the flu,and AIDS have in common?They're all diseases caused by viruses,tiny microorganisms that can pass from person to person. It's no wonder that when most people think about viruses,finding ways to steer clear of viruses is what's on people's minds.
Not everyone runs from the tiny disease carriers,though. In Cambridge,Massachu- setts,scientists have discovered that some viruses can be helpful in an unusual way. They are putting viruses to work,teaching them to build some of the world's smallest rechargeable batteries.
Viruses and batteries may seem like an unusual pair,but they're not so strange for engi-neer Angela Beicher,who first came up with the idea. At the Massachusetts Institute of
Technology(MIT)in Cambridge,she and her collaborators bring together different areas of science in new ways.In the case of the virus-built batteries,the scientists combine what they know about biology,technology and production techniques.
Beicher's team includes Paula Hammond,who helps put together the tiny batteries,and
Yet-Ming Chiang,an expert on how to store energy in the form of a battery.“We're working on things we traditionally don't associate with nature，”says Hammond.
Many batteries are already pretty small. You can hold A,C and D batteries in your hand. The coin-like batteries that power watches are often smaller than a penny. However, every year,new electronic devices like personal music players or cell phones get smaller than the year before. As these devices shrink,ordinary batteries won't be small enough to fit in-side.
The ideal battery will store a lot of energy in a small package. Right now,Belcher's model battery,a metallic disk completely built by viruses,looks like a regular watch battery. But inside,its components are very small一so tiny you can only see them with a powerful microscope.
How small are these battery parts?To get some idea of the size,pluck one hair from your head. Place your hair on a piece of white paper and try to see how wide your hair is一 pretty thin,right?Although the width of each person's hair is a bit different,you could probably fit about 10 of these virus-built battery parts,side to side,across one hair. These micro-batteries may change the way we look at viruses.
Which of the following is true of Belcher's battery mentioned in paragraph 6?
A: It is made of metal.
B: It is a kind of watch battery.
C: It can only be seen with a microscope.
D: It is a metallic disk with viruses inside it.

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Come out, or I 'll bust the door down.
A: shut
B:break
C: set
D:beat

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The Robot Man
According to Hans Moravec,universal robots will take over all the physical activities that we engage in,leaving us with little to do.Moravec sees four generations on the road to true universal robots. The first generation will be here by 2010 and will consist of free-ranging robots that can navigate by building an internal mental map of their surroundings.In new situations they'll be able to adapt,unlike today's mobile industrial robots.These robots will have the computing power to cope with simple speech and text recognition,and will be used for tasks such as domestic clean-ing.
The second generation will arrive around 2020 and will be distinguished by the ability to learn .Second generation robots are programmed with sets of primitive tasks and with feedback that provide"pleasure"and"pain"stimuli .For example,a collision provokes a negative response,a completed task would be positive.
Move forward another ten years to 2030 and you get to generation three.This robot can build internal simulations of the world around it. Before beginning a task,it can imagine what will happen in order to predict problems.If it has a free moment,it can replay past experiences and try variations in order to find a better way of如ing things next time .It could even observe a person or another robot performing a task and learn by imitation.For the first time,we have here a robot that can think.
By the time we get to generation four in 2040,Moravec predicts that robots will be able to: match human reasoning and behaviour;generalise abstract ideas from specific experience;and, conversely,compile detailed plans of action from general commands such as"earn a living"or "make more robots".
The Moravec manifesto（宣告）runs something like this. As robots start to become useful in generation one,they'll begin to take on many tasks in industry.Driven by the availability of this cheap and tireless labour force,the economy will boom and the demand for robots will grow so rapidly that they will soon become lowcost commodity items.So much so that they'll move into the home,where the domestic robot will relieve us of many chores.
With increasing automation in generations two and three,the length of the average working day will plummet,eventually to near zero. Most people will be unemployed as robots take over not just primary industry,but the service economy too.Moravec sees the fourth generation as an opportunity to surpass our human limitations.
These future machines will be our"mind children".Like biological children of previous generations,they will embody humanity's best hope for a long-term future.
The author's main purpose is to______.
A: describe the life of Hans Moravec
B: support the view that robots will play a major role in our life
C: make fun of the views of Hans Moravec
D: get people prepared for the threat of future robots

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第一篇
Almost Human?
Scientists are racing to build the world's first thinking robot.This is not science fiction:
some say they will have made it by the year 2020.Carol Packer reports.
Machines that walk,speak and feel are no longer science fiction.Kismet is the name
of an android（机器人）which scientists have built at the Massachusetts Institute of
Technology(MIT).Kismet is different from the traditional robot because it can show
human emotions.Its eyes,ears and lips move to show when it feels happy,sad or bored.
Kismet is one of the first of a new generation of androids一robots that look like human
beings一which can imitate human feelings.Cog,another android invented by the MIT,
imitates the action of a mother. However,scientists admit that so far Cog has the mental
ability of a two-year-old.
The optimists（乐观主义者）say that by the year 2020 we will have created humanoids
（机器人）with brains similar to those of an adult human being. These robots will be
designed to look like people to make them more attractive and easier to sell to the public.
What kind of jobs will they do?In the future,robots like Robonaut,a humanoid invented by
NASA,Will be doing dangerous jobs,like repairing space stations.They will also be doing
more and more of the household work for us.In Japan,scientists are designing androids
that will entertain us by dancing and playing the piano.
Some people worry about what the future holds:will robots become monsters（怪物）?
Will people themselves become increasingly like robots?Experts predict that more and more
people will be wearing micro-computers,connected to the Internet,in the future.People
will have micro-chips in various parts of their body,which will connect them to a wide variety
of gadgets（小装置）.Perhaps we should not exaggerate（夸大）the importance of
technology,but one wonders whether,in years to come,we will still be falling in love,
and whether we will still feel pain.Who knows?
In the future robots will also
A:explore space.
B:entertain people.
C:move much faster.
D:do all of the housework.

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Five minutes left,the outcome of the match was still in doubt.
A:result
B:judgment
C:decision
D:event

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The Greatest Mystery of Whales
The whale is a warm一blooded,air-breathing animal,giving birth to its young alive,sucking them一and,
like all mammals,originated on land. There are many________________(51)of this. Its front flippers（鳍状肢）,
used for steering and stability,are traces of feet.
Immense strength is________________(52)into the great body of the big whales,and in fact most of a
whale's body is one gigantic muscle.The blue whale's pulling strength has been estimated________________(53)
400 horsepower. One specimen was reported to have towed（拖）a whaling vessel for seven hours at the
_______________ (54)of eight knot（节）.
An angry whale will________________(55).A famous example of this was the fate of Whaler Essex,
________________(56)was sunk off the coast of South America early in the last century. More recently,steel ships
have ___________( 57 ) their plates buckled（使弯曲）in the same way. Sperm whales（抹香鲸）were known
to seize the old-time whaleboats in their jaws and crush them.
The greatest________________(58)of whales is their diving ability.The sperm whale dives to the bottom foi
his________________(59)food,the octopus（章鱼）.In that search he is known to go as far down as 3 , 200 feet,
where the________________(60)is 1,400 pounds,to a square inch.Doing so he will________________(61)underwa-
ter as long as one hour. Two special skills are involved in this storing up enough________________(62)(all
whales are air-breathed)and tolerating the great change in pressure.Just how he does it scientists have nol
_______________ (63).It is believed that some of the oxygen is stored in a special________________(64)of blood
vessels,rather than just held in the lungs.And it is believed that a special kind of oil in his head is some sort
of a compensating mechanism that________________(65)adjusts the internal pressure of his body.But since you
can't bring a live whale into the laboratory for study,no one knows just how these things work.
_________(56)
A:as
B:who
C:which
D:that

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