题目内容
An Interesting Phenomenon
The ability of falling cats to right themselves in midair and land on their feet has been a source of wonder for ages. Biologists long regarded it as an example of adaptation by natural selection, but for physicists it bordered on the miraculous. Newton’s laws of motion assume that the total amount of spin of a body can not change unless an external torque speeds it up or slows it down. If a cat has no spin when it is released and experiences no external toque, it ought not to be able to twist around as it falls.
In the speed of its execution, the righting of a tumbling cat resembles a magician’s trick. The gyrations of the cat in midair are too fast for the human eye to follow, so the process is obscured. Either the eye must be speeded up, or the cat’s fall be slowed down for the phenomenon to be observed. A century ago the former was accomplished by means of high - speed photography using equipment now available in any pharmacy. But in the nineteenth century the capture on film of a falling cat constituted a scientific experiment.
The experiment was described in a paper presented to the Paris Academy in 1894. Two sequences of twenty photographs each, one from the side and one from behind, show a white cat in the act of righting it self. Grainy and quaint though they are, the photos show that the cat was dropped upside down, with no initial spin, and still landed on its feet. Careful analysis of the photos reveals the secret: As the cat rotates the front of its body clockwise, the rear and tail twist counterclockwise, so that the total spin remains zero, in perfect accord with Newton’s laws. Halfway down, the cat pulls in its legs before reversing its twist and then extends them again, with the desired end result. The explanation was that while no body can acquire spin without torque, a flexible one can readily change its orientation, or phase. Cats know this instinctive ly, but scientists could not be sure how it happened until they increased the speed of their perceptions a thousand fold.
Why are the photographs mentioned referred to as an "experiment"？
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In order to get your point across in your target language, you have to learn plenty of words. How do you set about it？ Dr. Paul Meara, who lectures in applied linguistics, believes there are lots of different ways of learning words.
"Generally, anything you do with the words which actually makes them yours rather than just abstract things which appear in a book or on a record will almost certainly help you to learn them. So, for example, writing them down is better than reading them. Putting them on bits of paper and sticking them up around your house is better than just looking at them in the page of a book. Saying them out loud is better than reading them quietly. Anything which actually gets you to use them would probably help." Encouragement and nurturing in the students and belief in their ability to learn is one of the central tenets of a relatively new approach. It's called Accelerated Learning and it's an offshoot of an idea that began in Bulgaria. Michael Lawlor runs a language school for business executives, teaching foreign languages to the British, and English to foreigners. He's currently testing this system to see if he can incorporate it into his teaching program at his school. The main principle is to tap the students' emotions as well as their intellects and, to begin with, to get them to visualize themselves as successful communicators in the language they're learning.
"They can actually create a very clear mental picture of themselves say in five year's time, in the coun try where the language is spoken, interacting with the people. They can also boost their own confidence as learners by recreating past successful learning situation. Many people fail in learning a language because their minds get calmer and they provide their brains with oxygen. We teach them to sit properly so that they don't lose energy and maybe to have some simple physical movements to keep their energy up. All these things are part of the learning process."
The course work is based on puzzles and games and above all on bilingual dialogues, so there's no fear of not understanding. As the grammar is introduced, the rules are put into rhyming couplets to make them easier to remember. This method is all about reaching into the under-used resources of mind and memory. After a class, the students have a concert session when they hear the dialogue they were working on against a background of baroque music. Michael Lawlor explains why they used baroque music.
"Dr Lazanov in Bulgaria, in his original experiments, found that baroque music produced a state of relaxed awareness, which is now known more generally as the alpha state. If you take the large passages or the adagio passages from largo music, you find that they correspond more or less to the slowed-down speed of the human heart--about 60 beats to the minute. So we're helping people to slow down their body rhythms. The mind then becomes more receptive and open to passive learning, to listening. So that's why music of this kind is important. But it also, of course, touches the emotions. The music will induce a state of pleasurable expectation and if we can link the emotion of pleasure with learning, then we're making a very valuable contribution to the students' affective, or emotional, involvement with the learning process."
The Choice of a soft-spoken female voice to present the language in accelerated learning techniques is also deliberate. After all, who was it who taught you to speak your own language all those years ago？
Many people fail in learning a language because ______.
In the 1980's, real estate prices soared to super inflated levels, and investors sank their money into the booming stock market. There seemed to be no end in sight for the land of the rising sun. Everything was rising, and the government, financial institutions, and individuals paid little heed to the warning signs of an imminent crash. Then, the bubble burst, and land and stock prices plunged.
What is the result of the crash？ Many companies have faltered due to poor sales and bad debt, and have closed their doors. The domino effect on many financial institutions is that they must- bear an enormous number of unrecoverable loads, which have resulted when companies, depending on profits from land in vestments to repay loans, have fund themselves insolvent. Furthermore, many individual depositors, fearing a collapse of more banks and securities companies, have withdrawn their money in droves.
Attempts by tile government to revitalize the sluggish and contracting economy have proven fruitless. Pump-priming measures including tax cuts and public works spending have done little to put the economy on tract again. What's more, the government's decision to increase the consumption tax from 3 to 5 percent in 1997 has had a devastating impact on consumer spending. As for the business sector, companies have tried various measures to streamline management, but other ill effects of such policies, including rising unemployment among older workers, have surfaced and have dealt a huge blow to the recovery process,
Japan' s faltering economy has had an impact on other Asian countries, and some fear that the whole region will be drawn into depression. What will stem the tide of further economic collapse？ For one, Japan must stabilize its financial system and take immediate and effective measures to deal with non – performing loans. Revealing the severity of the problem to the public and foreign governments is an essential first step. A more vital solution might be to institute a permanent tax cut to stimulate consumer spending and confidence in the government' s handling of the situation. Ultimately, this will encourage domestic demand for goods and services and will be the driving force behind much of the recovery, That' s the bottom line. Of course, many more factors including deregulation will play a vital role in expediting economic stabilization and growth.
Whatever the case, action must be carried out swiftly and decisively. A passive and .reticent approach to reform. and change is what has hampered any improvement so far. Other nations have encouraged Japan to step up the pace of implementing change, but Japan must make the first step . . . or else we might be witnessing the setting of this great rising sun.
Japan's current economic crisis is the worst since ______.
听力原文： On December 25, 2000,. many Pe0Ple across North America received a rare Christmas treat when the moon passed in front of the sun resulting in a partial solar eclipse.
Solar eclipses occur when the moon passes between the earth and the sun, and the moon's shadow covers part of the earth, and a total solar eclipse takes place when the moon's shadow blocks out the sun entirely~ What made this particular solar eclipse unique was that such an event has occured on December twenty - fifth only 30 times during the past 5000 years, the last time in 1954. But people must be exceptionally careful when attempting to view a solar eclipse. Without taking precautionary measures, one can permanently damage the retina of the eyes; however, there are several safe methods of witnessing this heavenly marvel.
First, you can view a solar eclipse by using eclipse safety glasses for filtering out the sun's harmful rays. They should-be used when any part of the sun is visible. Sunglasses can block out some of the sun's ultraviolet rays, but the results can be very deceptive. The eye's natural reaction to this darken state when wearing sunglasses is to make the pupil larger, which allows in more light and can intensify the damage to your eyes. You can also watch an eclipse by pro- jecting the sun's image on a piece of paper either by using a telescope, or easier yet, by creating a pinhole in a piece of paper and viewing the result on another piece of paper, thus called a pinhole projector.
Only during a total eclipse when the sun is completely and briefly covered can you watch the eclipse without eye protection. Even then, extreme caution should be taken. In case you didn't catch this last spectacular eclipse on December twenty - fifth, 2000, there's no need to fret. Your posterity can record the next eclipse on Christmas in the year 2307, but only if their visiting the west coast of Africa for the holidays.
What made this eclipse so unique？
3D.H. Lawrence ascribed the alienation of the human relationships and the perversion of human personality to______.
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