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共用题干
Women's minds work differently from men's.At least,that is what most men are convinced of. Psychologists view the subject either as a matter of frustration or a joke.Now the biologists have moved into this minefield,and some of them have found that there are real differences between the brains of men and women.But being different,they point out hurriedly,is not the same as being better or worse.
There is,however,a definite structural variation between the male and female brain.The difference is in a part of the brain that is used in the most complex intellectual processes一the link between the two halves of the brain.
The two halves are linked by a trunk line of between 200 and 300 million nerves,the corpus callosum.Scientists have found quite recently that the corpus callosum in women is always larger and probably richer in nerve fibres than it is in men.This is the first time that a structural difference has been found between the brains of women and men and it must have some significance.The question is"What?",and,if this difference exists,are there others?Research shows that present-day women think differently and behave differently from men.Are some of these differences biological and inborn,a result of evolution?We tend to think that is the influence of society that produces these differences.But could we be wrong?
Research showed that these two halves of the brain had different functions,and that the corpus callosum enabled them to work together. For most people,the left half is used for word-handling, analytical and logical activities;the right half works on pictures,patterns and forms.We need both halves working together. And the better the connections,the more harmoniously the two halves work.And,according to research findings,women have the better connections.
But it isn't all that easy to explain the actual differences between skills of men and women on this basis.In schools throughout the world girls tend to be better than boys at"language subjects" and boys better at maths and physics.If these differences correspond with the differences in the hemispheric trunk line,there is an unalterable distinction between the sexes.
We shan't know for a while,partly because we don't know of any precise relationship between abilities in school subjects and the functioning of the two halves of the brain,and we cannot understand how the two halves interact via the corpus callosum.But this striking difference must have some effect and,because the difference is in the parts of the brain involved in intellect,we should be looking for differences in intellectual processing.
According to the passage it is commonly believed that brain differences are caused by social factors.
A:Right
B:Wrong
C:Not mentioned
共用题干
Cell Phone Lets Your Secret Out
Your cell phone holds secrets about you.Besides the names and _____________(51)that you've pro-
grammed into it,traces of your DNA linger on the device,according to a new study.
DNA is genetic material that______________(52)in every cell.Like your fingerprint,your DNA is unique
to you一 _____________（53)you have an identical twin.Scientists today routinely analyze DNA in blood,
saliva,or hair left _____________(54)at the scene of a crime.The results often help detectives identify
_____________(55)and their victims.Your cell phone can reveal more about you _____________(56)you might
think.
Meghan J.McFadden,a scientist at McMaster University in Hamilton,Ontario,heard about a crime in
which the suspect bled onto a cell phone and later dropped the______________(57).This made her wonder
whether traces of DNA lingered on cell phones even when no blood was involved.______________(58)she and
colleague Margaret Wallace of the City University of New York analyzed the flip-open phones of 10 volun-
teers.They used swabs to collect______________(59)traces of the users from two parts of the phone:the
outside,where the user holds it,and the______________(60),which is placed at the user's ear.
The scientists scrubbed the phones using a solution made mostly______________(61)alcohol.The aim of
washing was to remove all detectable traces of DNA.The owners got their phones______________(62)for
another week.Then the researchers collected the phones and repeated the swabbing of each phone once
more.
The scientists discovered DNA that _____________(63)to the phone's speaker on each of the phones.
Better samples were collected from the outside of each phone,but those swabs also picked up DNA that be-
longed to other people who had apparently also handled the phone.______________(64),DNA showed up even
in swabs that were taken immediately after the phones were scrubbed.That suggests that washing won't remove
all traces of evidence from a criminal's device.So cell phones can now be added to the
______________(65)of clues
that can clinch a crime-scene investigation.
_________(62)
A:upon
B:back
C:without
D:with
共用题干
Look After Your Voice
Often speakers at a meeting experience dry mouths and ask for a glass of water. You can solve the
problem by activating the saliva in your mouth.First gently bite the edges of your tongue with your teeth.Or,
press your entire tongue to the bottom of your mouth and hold it there until the saliva flow. Or you can
imagine that you are slicing a big juicy lemon and sucking the juice.
Before you begin your talk,be kind to your voice.Avoid milk or creamy drinks which coat your throat.
Keep your throat wet by drinking a little sweetened warm tea or diluted fruit juice.
If you sense that you are losing your voice,stop talking completely.Save your voice for your speech.You
may feel foolish using paper to write notes,but the best thing you can do is to rest your voice.If you need to
see a doctor.perhaps you can get some advice from a orofessional singer. In the meantime,do not even talk in
a low voice.
What about drinking alcohol to wet your throat?I advise you not to touch alcohol before speaking.The
problem with alcohol is that one drink gives you a little confidence.The second drink gives you even more
confidence.Finally you will feel all-powerful and you will feel you can do everything,but in fact your brain
and your mouth do not work together properly.Save the alcohol until after you finish speaking.
Perhaps you want to accept the advice, but you may wonder if you can ever change the habits of a
lifetime.Of course you can.Goethe,who lived before indoor skating rinks or swimming pools,said,"We learn
to skate in the summer and swim in the winter."Take this message to heart and give yourself time to develop
your new habits.If you are willing to change,you will soon be able. to say that you will never forget these
techniques because they became a part of your body.
The first paragraph mentions three ways of activating the saliva in the mouth.
A:Right
B:Wrong
C:Not mentioned
共用题干
Electromagnetic Energy
1 White light seems to be a combination of all colors.The energy that comes from a source of light is
not limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy
day it is possible to get a sunburn even though you feel cool.Visible light and the kind of energy that produce
warmth and sunburn are examples of electromagnetic energy.
2 The sun is 93 million miles away from the earth.Yet we can use energy from the sun because elec-
tromagnetic energy travels through space.
3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signals
travel from transmitters to receivers as low-energy electromagnetic waves. Infrared（红外线的）radiation is an
electromagnetic wave.When it is absorbed by matter,heat is produced.Waves of infrared and visible light
have more energy than waves of radio , television , or radar. Ultraviolet rays（紫外线）and X-rays are electro-
magnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating
buildings.Sunlight and electric lights are part of our requirements for normal living. Ultraviolet radiation is
useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel right
through solid objects.They can be used to detect and treat cancer. X-rays are used in industry to find hidden
cracks in metal,and in medicine to reveal broken bones.
4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the
sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is
trapped behind dams and then used to operate electric generators.Other generators are powered by coal,but
the energy stored in coal came from the sun,too.
5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If
the.sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with
electromagnetic radiation led to the theory that mass can be converted into energy.About forty years after the
theory was proposed , nuclear energy was harnessed（利用）by man. Chemical energy comes from electron
（电子）rearrangement. Nuclear energy comes from a change in the nucleus of an atom. Compared with chemi-
cal reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that
the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.
6 Nuclear energy is beginning to compete with coal as an economical source of power to generate elec-
tncity.It is also being used to operate engines in large ships.Scientists continue to seek new and better
methods of obtaining and using energy.
Paragraph 3_____________
A:Nuclear Reactions as the Lasting Source of the Sun's Energy
B:The Most Important Source of Energy
C:Types of Electromagnetic Energy
D:X-rays Are Used to Detect and Treat Cancer
E:Seeking New Sources of Energy
F:Nuclear Energy Is Beginning to Compete With Coal
共用题干
How Men Face the Fat Problem
It is a pleasure to see men of a certain age worrying about their weight. Listening to them is not such a pleasure.Because the men are new at the game,they don't hesitate to discuss the fat problem incessantly. However,women of the same age do not discuss the fat problem,especially not in mixed company. They prefer to face the problem with quiet dignity.Discussing the problem might only draw attention to some stray body part that may be successfully tucked away under an article of clothing.
The age at which a man begins to explore the fat problem can vary.The actual problem can manifest itself in the early 30's,but broad-range discussion usually starts later. There are early nonverbal symptoms.I've watched the rugged journalist who shares my apartment sneak by with a Diet Coke.His shirts are no longer neatly tucked in to display a trim waist. Recently he has begun to verbalize his anxiety.He tells me,with a sheepish幼n,that he is taking his suits to Chinatown to have them"tailored."
Still-older men have lost their dignity and rattle on unabashedly. Often,wives and children play important roles in their fat-inspection rituals.Take my oldest brother,a former college football player. His daughter says that several times a day he will stand at attention and call out,"Fat,medium or thin?"She knows the correct answer:medium. Thin would be an obvious stretch,and fat may not get her that new video.According to his wife,he stands in front of the mirror in the morning (before the day's meals take their toll),puts his hands behind his head and lurches into a side bend,then clutches the roll that has developed and says,"Am I getting fatter?"His wife is expected to answer,"You look like you may have lost a few pounds."
And then there are the ex-husbands,a pitiful group.They are extremely vocal.When I go to the movies with one,he confides that he is suffering from great hunger because he is dieting.He hasn't eaten since the pancakes and sausages he wolfed down that morning. He pauses in his monologue while he buys his popcorn.After the movie,we sprint to a restaurant,where he again pauses to devour a basket of bread.Before he orders his chaste salad and soup,he grows plaintive.Do I think he's fat?
Men of a certain age are always ready to talk about their fat problem.
A:Right
B:Wrong
C:Not mentioned
