Not long ago, some of you may have read about the team of mountain-climbing scientists who helped to recalculate the elevation of the highest mountain in the world, Mount Everest. Of course the elevation of Mount Everest was determined many years ago using traditional surveying methods. But these scientists wanted to make a more precise measurement, using a new method that takes advantage of recent advances in technology: it’s called the Global Positioning System. The Global Positioning System uses 24 satellites that circle the earth. Each of the satellites is constantly sending out signals, and each signal contains important information that can be used to determine the longitude, latitude and elevation at any point on the earth’s surface. Well, in order to use this system to calculate Mount Everest’s elevation, scientists need to put a special receiver on its summit to receive signals from the satellites. The problem with this was that in the past, the receivers were much too heavy for climbers to carry. But now these receivers have been reduced to about the size and weight of a hand-held telephone, so climbers were able to take the receiver to the top of the Everest, and from there, to access the satellite system signals that would allow them to determine the precise elevation. And it turns out that the famous peak is actually a few feet higher than was previously thought. 15. What is the talk mainly about? 16. Why does the speaker mention a hand-held telephone? 17. According to the talk, what probably contributed most to the success of the new study of Mount Everest? 18. In the study described, how were satellites’ signals used? The advantages of traditional surveying methods. Using satellites to communicate with mountain climbers. Obtaining new information about a mountain. Controlling satellites from the top of a mountain.

Stocks, bonds, land—people invest in different things and【C1】______. But all investors【C2】______. They want to get more money out of their investment than they put into it. The money they invest today【C3】______for future growth in the economy. But people can watch their own【C4】______take a wild ride as markets rise and fall. So investors have to decide【C5】______they are willing to take and for how long. One choice for many people who want a【C6】______investment is the money market. Usually individuals do this through money market mutual funds. Mutual funds are investment pools. They【C7】______many investors. Money market mutual funds earn interest from【C8】______to government and businesses. But the return to investors is low because little risk is involved.【C9】______are loans, too. They have terms from 【C10】______. The longer the term of a loan, the greater the risk that the investment will not be【C11】______. So notes and bonds usually pay higher interest rates than short-term bills or【C12】______. Millions of people invest in bonds and other debt-based products. This is true especially as people【C13】______and want to reduce the level of risk in their investments. But over time, debt-based investments have【C14】______provided lower returns than stocks. Stock is a share of【C15】______in a business. Common stock gives investors a vote on company【C16】______. It might also pay a small percentage of【C17】______, a dividend, one or more times a year. Not all stocks pay dividends. Some are valued more【C18】______. Investing in stocks of individual companies can be very risky. Bad news can quickly【C19】______. Instead, many people invest in stock mutual funds so their money goes into many different stocks.【C20】______mix stocks and bonds to spread risk— and capital—even more.Stocks, bonds, land—people invest in different things and for different reasons. But all investors share the same goal. They want to get more money out of their investment than they put into it. The money they invest today provides capital for future growth in the economy. But people can watch their own financial future take a wild ride as markets rise and fall. So investors have to decide how much risk they are willing to take and for how long. One choice for many people who want a low-risk investment is the money market. Usually individuals do this through money market mutual funds. Mutual funds are investment pools. They gather the money of many investors. Money market mutual funds earn interest from short-term loans to government and businesses. But the return to investors is low because little risk is involved. Notes and bonds are loans, too. They have terms from two to thirty years. The longer the term of a loan, the greater the risk that the investment will not be repaid. So notes and bonds usually pay higher interest rates than short-term bills or commercial paper. Millions of people invest in bonds and other debt-based products. This is true especially as people get older and want to reduce the level of risk in their investments. But over time, debt-based investments have traditionally provided lower returns than stocks. Stock is a share of ownership in a business. Common stock gives investors a vote on company issues and leadership. It might also pay a small percentage of its value, a dividend, one or more times a year. Not all stocks pay dividends. Some are valued more for their growth. Investing in stocks of individual companies can be very risky. Bad news can quickly cut their value. Instead, many people invest in stock mutual funds so their money goes into many different stocks. Balanced funds mix stocks and bonds to spread risk—and capital—even more.

1. John and Lisa’s skills are complementary: she’s good at routine work while he’s great at handling emergencies. Together they make a great team. 2. Even if Sark said those harsh things, he didn’t expect you to take it personally. 3. Henry is the eldest son of the old man who just died, hence he is the heir to the large fortune. 4. Please pay attention now. The departure gate of Flight A32 has been changed from 29F to 30B. 5. Donald said that he and Francie got divorced last autumn, nevertheless I’m sure they aren’t. John and Lisa are team members. John and Lisa are good at handling emergencies. John and Lisa are good at routine work. John and Lisa are good partners when working together.

M: Hey, Kelly. Looks like you got some sun this weekend. W: Yeah, I guess so. I spent the weekend at the beach. M: Oh yeah? That’s great! Where did you stay? W: Some friends of my parents live out there and they invited me for as long as I wanted to stay. M: So what are you doing back here already? W: Oh, I have a paper I need to work on, and I just couldn’t do any serious studying at the beach. M: I don’t blame you. So what did you do out there... I mean besides lie out in the sun, obviously? W: I jogged up and down the beach and I played some volleyball. You know, I never realized how hard it is to run on sand. I couldn’t even get through a whole game before I had to sit down. It’s much easier to run in the wet sand near the water. M: Not to mention cooler. Did you go swimming? W: I wanted to, but they said the water isn’t warm enough for that until a couple months from now, so I just waded in up to my knees. M: It all sounds so relaxing. I wish I could get away to the beach like that. W: It looks like you could use it. Don’t tell me you spent the weekend in the library again. 11. How did the woman spend last weekend? 12. Why did the woman come home so soon? 13. Why did the woman have to stop playing in the volleyball game? 14. Why didn’t the woman go swimming? Relaxing at the seashore. Visiting her parents. Sailing on a boat. Preparing for a race.

M: Mrs. Wolper, why is it that some children perform much better than others at school? W: Obviously, it can’t be denied that certain children are brighter than others, but it’s not as simple as that. A lot of emphasis is placed on intelligence measured by tests—so-called IQ tests, which only measure certain types of intelligence. M: Such as? W: Basically linguistic and numerical skills, or reading and mathematics, which is unfortunate because some children are bound to suffer. A good example was a friend of mine’s son who was kept out of the top class at school because of his average IQ. His father, though he had no idea his son was going to be an architect, always said he was a clever child. Apparently he was able to picture things in his mind and draw accurately at a very early age. The point is that his university life might not have been so difficult if his ability had been recognized sooner. M: What you’re saying, then, is that some children have ability that is not easy to measure, that aren’t appreciated by many schools. W: Precisely. And if these skills are not spotted sufficiently early, they can’t be developed. That’s why there are so many unhappy adults in the world. They are not doing the things they are best at. M: What are these other kinds of intelligence, and how can we recognize them in our children? W: Well, take musical talent as an example. Many children never get the chance to learn to play an instrument but, while they might not become great artists or composers, they may get a lot of pleasure and satisfaction. Musically gifted children are fascinated by all kinds of sounds—car horns, animal noises and so on. And they can easily recognize tunes and sing them in key. M: How can a parent encourage them? W: Sing to them and teach them new songs. Buy a piano or even a cheap instrument such as a recorder. If you can afford it, send them to lessons as soon as possible. Play records of different instruments to them. M: What about a child who is good at sport or other things? I’m so sorry because our time is almost up, could you please make a brief summary? W: Hardly anyone is good at everything. So in my opinion, a child should be judged on his individual talents. After all, being happy in life is putting your skills to good use, no matter what they are. 19. According to the talk, what is Mrs. Wolper? 20. What is IQ test? 21. How are musically gifted children different from others? 22. According to Mrs. Wolper, what is the correct attitude towards a child’s talent? A primary school teacher. A doctor. A psychologist. A musician.

M: Thanks for stopping by, Betty. I’d like to talk to you about a research project I thought you might be interested in. A friend of mine is working at Yellowstone National Park this summer... W: Yellowstone! I’ve always wanted to spend some time out in Wyoming. M: Wait till you hear what the project is... She’s working with the buffalo population. The herds have been increasing in size lately, which is good in theory... W: Yeah...but I thought they were in danger of becoming extinct. M: Well, apparently, because of all the winter tourists, paths are created in the snow. More buffalo are surviving the harsh winters because the paths make it easier for the buffalo to move around and find food. But it turns out that some of the herds are infected with a bacteria. W: Oh yeah, I heard about that. Bru... M: Brucella abortus. W: Right, it’s been.around for quite a while. M: Yes, it has. And because the buffalo population is increasing, they’ve been roaming more than usual, the disease has begun to spread to the cattle ranches that border the park. W: That’s bad news! Isn’t that the disease that causes animals to abort their young? M: Yes, and it’s caused a lot of controversy. Some of the ranchers even want to destroy the buffalo herds. W: That’s awful! Have they made much progress with the research? M: So far, they’ve been collecting tissue samples from dead buffalo to see if the bacteria’s present. W: I’d really be interested in working on this. You know, I’ve been researching diseased animal populations... M: That’s why I thought of you... I took the liberty of mentioning your name to my friend. She’s hoping you’ll be able to spend the whole summer out there. W: Well, I was going to work on my thesis a lot in July, but I’m sure my adviser wouldn’t want me to pass up this opportunity. 27. What does the professor want to talk to Betty about? 28. According to the professor, why is the buffalo population increasing? 29. Why does the professor think Betty would be interested in going to Yellowstone? 30. How will Betty probably spend the summer? A vacation trip to Yellowstone Park. A lecture by a visiting professor. Her biology thesis. A research project.

Recent years have brought minority-owned businesses in the United States unprecedented opportunities as well as new and significant risks. Civil rights activists have long argued that one of the principal reasons why Blacks, Hispanics, and other minority groups have difficulty establishing themselves in business is that they lack access to the sizable orders and subcontracts that are generated by large companies. Now Congress, in apparent agreement, has required by law that businesses awarded federal contracts of more than $500,000 do their best to find minority subcontractors and record their efforts to do so on forms filed with the government. Indeed, some federal and local agencies have gone so far as to set specific percentage goals for apportioning part of public works contracts to minority enterprises. Corporate response appears to have been substantial. According to figures collected in 1977, the total of corporate contracts with minority businesses rose from $77 million in 1972 to $1.1 billion in 1977. The projected total of corporate contracts with minority businesses for the early 1980s is estimated to be over $3 billion per year with no letup anticipated in the next decade. Promising as it is for minority businesses, this increased patronage poses dangers for them, too. First, minority firms risk expanding too fast and overextending themselves financially, since most are small concerns and, unlike large businesses, they often need to make substantial investments in new plants, staff, equipment, and the like in order to perform work subcontracted to them. If, thereafter, their subcontracts are for some reason reduced, such firms can face potentially crippling fixed expenses. The world of corporate purchasing can be frustrating for small entrepreneurs who get requests for elaborate formal estimates and bids. Both consume valuable time and resources, and a small company’s efforts must soon result in orders, or both the morale and the financial health of the business will suffer. A second risk is that White-owned companies may seek to cash in on the increasing apportionments through formation of joint ventures with minority-owned concerns. Of course, in many instances there are legitimate reasons for joint ventures: clearly, white and minority enterprises can team up to acquire business that neither could acquire alone. But civil rights groups and minority business owners have complained to Congress about minorities being set up as “fronts“ with White backing, rather than being accepted as full partners in legitimate joint ventures. Third, a minority enterprise that secures the business of one large corporate customer often run the danger of becoming and remaining dependent. Even in the best of circumstances, fierce competition from larger, more established companies makes it difficult for small concerns to broaden their customer bases: when such firms have nearly guaranteed orders from a single corporate benefactor, they may truly have to struggle against complacency arising from their current success.

No very satisfactory account of the mechanism that caused the formation of the ocean basins has yet been given. The traditional view supposes that the upper mantle of the earth behaves as a liquid when it is subjected to small forces for long periods and that differences in temperature under oceans and continents are sufficient to produce convection in the mantle of the earth with rising convection currents under the mid-ocean ridges and sinking currents under the continent. Theoretically, this convection would carry the continental plates along as though they were on a conveyer belt and would provide the forces needed to produce the split that occurs along the ridge. This view may be correct: it has the advantage that the currents are driven by temperature differences that themselves depend on the position of the continents. On the other hand, the theory is implausible because convection does not normally occur along lines, and it certainly does not occur along lines broken by frequent offsets or changes in direction, as the ridge is. It has the advantage that the currents are driven by temperature differences that themselves depend on the position of the continents. Such a back-coupling, in which the position of the moving plate has an impact on the forces that move it, could produce complicated and varying motions. Also it is difficult to see how the theory applies to the plate between the Mid-Atlantic Ridge and the ridge in the Indian Ocean. This plate is growing on both sides, and since there is no intermediate trench, the two ridges must be moving apart. It would be odd if the rising convection currents kept exact pace with them. An alternative theory is that the sinking part of the plate, which is denser than the hotter surrounding mantle, pulls the rest of the plate after it. Again it is difficult to see how this applies to the ridge in the South Atlantic, where neither the African nor the American plate has a sinking part. Another possibility is that the sinking plate cools the neighboring mantle and produces convection currents that move the plates. This last theory is attractive because it gives some hope of explaining the enclosed seas, such as the Sea of span. These seas have a typical oceanic floor, except that the floor is overlaid by several kilometers of sediment. Their floors have probably been sinking for long periods. These seas have a typical oceanic floor, except that the floor is overlaid by several kilometers of sediment. Their floors have probably been sinking for long periods. It seems possible that a sinking current of cooled mantle material on the upper side of the plate might be the cause of such deep basins. The enclosed seas are an important feature of the earth’s surface and seriously require explanation because, in addition to the enclosed seas that are developing at present behind island arcs, there are a number of older ones of possibly similar origin, such as the Gulf of Mexico, the Black Sea, and perhaps the North Sea.

Prior to 1975, union efforts to organize public-sector clerical workers, most of whom are women, were somewhat limited. The factors favoring unionization drives seem to have been either the presence of large numbers of workers, as in New York City, to make it worth the effort, or the concentration of small numbers in one or two locations, such as a hospital, to make it relatively easy. Receptivity to unionization on the workers’ part was also a consideration, but when there were large numbers involved or the clerical workers were the only unorganized group in a jurisdiction, the multioccupational unions would often try to organize them regardless of the workers’ initial receptivity. The strategic reasoning was based, first, on the concern that politicians and administrators might play off unionized against nonunionized workers, and, second, on the conviction that a fully unionized public work force meant power, both at the bargaining table and in the legislature. In localities where clerical workers were few in number, were scattered in several workplaces, and expressed no interest in being organized, unions more often than not ignored them in the pre-1975 period. But since the mid-1970s, a different strategy has emerged. In 1977, 34 percent of government clerical workers were represented by a labor organization, compared with 46-percent of government professionals, 44 percent of government blue-collar workers, and 41 percent of government service workers. Since then, however, the biggest increases in public-sector unionization have been among clerical workers. Between 1977 and 1980, the number of unionized government workers in blue-collar and service occupations increased only about 1.5 percent, while in the white-collar occupations the increase was 20 percent and among clerical workers in particular, the increase was 22 percent. What accounts for this upsurge in unionization among clerical workers? First, more women have entered the work force in the past few years, and more of them plan to remain working until retirement age. Consequently, they are probably more concerned than their predecessors were about job security and economic benefits. Also, the women’s movement has succeeded in legitimizing the economic and political activism of women on their own behalf, thereby producing a more positive attitude toward unions. The absence of any comparable increase in unionization among private-sector clerical workers, however, identifies the primary catalyst—the structural change in the multioccupational public-sector unions themselves. Over the past twenty years, the occupational distribution in these unions has been steadily shifting from predominantly blue-collar to predominantly white-collar. Because there are far more women in white-collar jobs, an increase in the proportion of female members has accompanied the occupational shift and has altered union policy-making in favor of organizing women and addressing women’s issues.

亚洲地域辽阔、资源丰富、人口众多、历史悠久、文化灿烂。20世纪中叶以后，亚洲绝大多数国家赢得了独立、和平与安宁。不少国家和地区实现了经济跨越式发展，新兴工业化国家和地区相继崛起，越来越多的亚洲人民开始过上好日子。2000年以来，亚洲国内生产总值年均增长超过6％，对世界经济增长的贡献率平均达到20％。目前，亚洲经济总量占全球的四分之一，贸易总额占全球的三分之一，外汇储备占全球的四分之三。

In general, our society is becoming one of giant enterprises directed by a bureaucratic management in which man becomes a small well-oiled cog in the machinery. The oiling is done with higher wages, well-ventilated factories and piped music, and by psychologists and “human relations“ experts: yet all this oiling does not alter the fact that man has become powerless, that he is bored with it. In fact, the blue—and the white-collar workers have become economic puppets who dance to the tune of automated machines and bureaucratic management. The worker and employee are anxious not only because they might find themselves out of a job: they are anxious also because they are unable to acquire any real satisfaction of interest in life. They live and die without ever having confronted the fundamental realities of human existence as emotionally and intellectually independent and productive human beings. Those higher up on the social ladder are no less anxious. Their lives are no less empty than those of their subordinates. They are even more insecure in some respects. They are in a highly competitive race. To be promoted or to fall behind is not a matter of salary but even more a matter of self-respect. When they apply for their first job, they are tested for intelligence as well as for the right mixture of submissiveness and independence. From that moment on they are tested again and again—by the psychologists, for whom testing is a big business, and by their superiors, who judge their behavior, sociability, capacity to get along, etc. This constant need to prove that one is as good as or better than one’s fellow-competitor creates constant anxiety and stress, the very causes of unhappiness and illness. Am I suggesting that we should return to the pre-industrial mode of production or to nineteenth-century “free enterprise“ capitalism? Certainly not. Problems are never solved by returning to a stage which one has already outgrown. I suggest transforming our social system from a bureaucratically managed industrialism in which maximal production and consumption are ends in themselves into a humanist industrialism in which man and full development of his potentialities—those of all love and of reason—are the aims of social arrangements. Production and consumption should serve only as means to this end, and should be prevented from ruling man.

6. They would have been here with us by now, if they had caught the early train. 7. Despite all the evidence Monica had gathered, Mark refused to admit that she was right. 8. The balance in your bank account is 15,000 dollars only, and so this check in the amount of 20,000 dollars has to be bounced. 9. Bill Gates didn’t finish his undergraduate study, therefore some young students fantasize that they can also become millionaires if they drop out. 10. Demand for specialized technical skills has long exceeded the supply of native-born workers with advanced degrees, and scientists and engineers from other countries fill this gap. They are here with us now because they took the early train. They wanted to be with us, so they took the early train. They didn’t take the early train, so they can’t be here now. Even if they took the early train, they still couldn’t be with us now.

We know then that in the US, it’s the job of Congress to review proposed new laws, which we call bills, and perhaps to modify these bills and then wrote on them. But even if the bill passed in Congress, it still doesn’t become a law until the president had a chance to review it, too. And if it’s not to the president’s liking, the bill can be vetoed or killed in either of two ways. One is by a veto message. The president has ten days to veto the bill by returning it to Congress, along with the message explaining why it’s being rejected. This keeps the bill from becoming a law unless overwhelming majorities of both Houses of Congress vote to over-right the president’s veto. Something they really do. Often, lawmakers simply revised the vetoed bill and passed it again. This time, in the form the president less likely to object to, and thus less likely to want to veto. The other way the president can kill a bill is by pocket veto. Here’s what happens. If the president doesn’t sign the bill within ten days, and Congress are jurors during that time, then the bill will not become law. Notice that is only the end of entire session of Congress that the pocket veto can be used, not just whenever Congress take the shorter break, say, for a summer vacation. After a pocket veto, that particular bill is dead. If a lawmaker in Congress wants to push the matter in their next session, they’ll have to start all over with a brand new version of the bill. 23. What is the main topic of the talk? 24. What does a veto message explain? 25. What do lawmakers often do after a veto message is issued? 26. What happens to a bill as the result of a pocket veto? How the president proposes new laws. How a bill is passed by lawmakers in Congress. How the president can reject a proposed law. How the president usually signs a bill.

(1)Traditionally, the father’s family name is the first choice for a Chinese kid’s surname, although the use of the mother’s name is not uncommon. (2)Eating a first course of soup before lunch, people can reduce their total calorie intake by 20%, compared with those who do not begin the meal with soup. (3)Few days go by without a mention of globalization in the media. While we are all aware that globalization is affecting our lives, our attitudes to it differ widely. (4)If the stock market declines by 40%, then people feel less wealthy: if they feel less wealthy, they buy less: if they buy less, less is produced and fewer people are employed. (5)Making sure military mothers have the quality child care, generous family leave, and access to necessary mental health services is key to their family well-being and national security.

(1)Apart from their love for Chinese cuisine, now more Americans are turning to its acupuncture, herbal medicines, martial arts, and kongfu films. Chinese language is now taught in many leading US universities. With the growing popularity of Chinese things, China emerges as a potential world political and economic superpower. This coincides with its reopening to the outside world. (2)It is a common wish of everyone to be successful and excellent. Is there a formula to achieving success and excellence? I would like to refer to the two P’s and two C’s here. The two P’s refer to Perspiration and Perseverance. The two C’s are Curiosity and Courage. Today, I would like to expand on curiosity and courage.

I am one of the many city people who are always saying that given the choice we would prefer to live in the country away from the dirt and noise of a large city. I have managed to convince myself that if it weren’t for my job I would immediately head out for the open spaces and go back to nature in some sleepy village buried in the county. But how realistic is the dream? Cities can be frightening places. The majority of the population live in massive tower blocks, noisy, dirty and impersonal. The sense of belonging to a community tends to disappear when you live fifteen floors up. All you can see from your window is sky, or other blocks of flats. Children become aggressive and nervous—cooped up at home all day, with nowhere to play: their mothers feel isolated from the rest of the world. Strangely enough, whereas in the past the inhabitants of one street all knew each other, nowadays people on the same floor in tower blocks don’t even say hello to each other. Country life, on the other hand, differs from this kind of isolated existence in that a sense of community generally binds the inhabitants of small villages together. People have the advantage of knowing that there is always someone to turn to when they need help. But country life has disadvantages too. While it is true that you may be among friends in a village, it is also true that you are cut off from the exciting and important events that take place in cities. There’s little possibility of going to a new show or the latest movie. Shopping becomes a major problem, and for anything slightly out of the ordinary you have to go on an expedition to the nearest large town. The city-dweller who leaves for the country is often oppressed by a sense of unbearable stillness and quiet. What, then, is the answer? The country has the advantage of peace and quiet, but suffers from the disadvantage of being cut off: the city breeds a feeling of isolation, and constant noise batters the senses. But one of its main advantages is that you are at the centre of things, and that life doesn’t come to an end at half past nine at night. Some people have found(or rather bought)a compromise between the two: they have expressed their preference for the “quiet life“ by leaving the suburbs and moving to villages within commuting distance of large cities. They generally have about as much sensitivity as the plastic flowers they leave behind—they are polluted with strange ideas about change and improvement which they force on to the unwilling original inhabitants of the villages. What then of my dreams of leaning on a cottage gate and murmuring “morning“ to the locals as they pass by. I’m keen on the idea, but you see there’s my cat, Toby. I’m not at all sure that he would take to all that fresh air and exercise in the long grass. I mean, can you see him mixing with all those hearty males down the farm? No, he would rather have the electric imitation-coal fire any evening.

Traveling through the country a couple of weeks ago on business, I was listening to the talk of the late UK writer Douglas Adams’ master work The Hitchhiker’s Guide to the Galaxy on the radio and thought—I know, I’ll pick up the next hitchhikers I see and ask them what the state of real hitching is today in Britain. I drove and drove on main roads and side roads for the next few days and never saw a single one. When I was in my teens and 20s, hitchhiking was a main form of long-distance transport. The kindness or curiosity of strangers took me all over Europe, North America, Asia and southern Africa. Some of the lift-givers became friends, many provided hospitality on the road. Not only did you find out much more about a country than when traveling by train or plane, but there was that element of excitement about where you would finish up that night. Hitchhiking featured importantly in Western culture. It has books and songs about it. So what has happened to it? A few years ago, I was asked the same question about hitching in a column of a newspaper. Hundreds of people from all over the world responded with their view on the state of hitchhiking. Rural Ireland was recommended as a friendly place for hitching, as was Quebec, Canada—“if you don’t mind being criticized for not speaking French“. But while hitchhiking was clearly still alive and well in some places, the general feeling was that throughout much of the west it was doomed. With so much news about crime in the media, people assumed that anyone on the open road without the money for even a bus ticket must present a danger. But do we need to be so wary both to hitch and to give a lift? In Poland in the 1960s, according to a Polish woman who e-mailed me, “the authorities introduced the Hitchhiker’s Booklet. The booklet contained coupons for drivers, so each time a driver picked somebody, he or she received a coupon. At the end of the season, drivers who had picked up the most hikers were rewarded with various prizes. Everyone was hitchhiking then.“ Surely this is a good idea for society. Hitchhiking would increase respect by breaking down barriers between strangers. It would help fight global warming by cutting down on fuel consumption as hitchhikers would be using existing fuels. It would also improve educational standards by delivering instant lessons in geography, history, politics and sociology. A century before Douglas Adams wrote his Hitchhiker’s Guide, another adventure story writer, Robert Louis Stevenson, gave us that what should be the hitchhiker’s motto: “To travel hopefully is a better thing than to arrive. “ What better time than putting a holiday weekend into practice. Either put it to the test yourself, or help out someone who is trying to travel hopefully with thumb outstretched.

Just how salt became so crucial to our metabolism is a mystery: one appealing theory traces our dependence on it to the chemistry of the late Cambrian seas. It was there, a half billion years ago, that tiny metazoan organisms first evolved systems for sequestering and circulating fluids. The water of the early oceans might thus have become the chemical prototype for the fluids of all animal life—the medium in which cellular operations could continue no matter how the external environment changed. This speculation is based on the fact that, even today, the blood serums of radically divergent species are remarkably similar. Lizards, platypuses, sheep, and humans could hardly be more different in anatomy or eating habits, yet the salt content in the fluid surrounding their blood cells is virtually identical. As early marine species made their way to fresh water and eventually to dry land, sodium remained a key ingredient of their interior, if not their exterior, milieu.