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Feed the World with Potatoes1 As food prices continue to rise rapidly, there is growing concern about the effect it will have among the world"s poor.2 Increasingly, experts are looking to the potato as a possible low-cost solution to feeding the hungry. To emphasize the issue, the United Nations has called the potato "a hidden treasure", and named 2008 the International Year of the Potato. Here"s how potatoes could end the food crisis.3 The potato matures more quickly, on less land and in harsher climates than most other major crops. Up to 85 percent of the plant is eatable, compared with around 50 percent of cereals. Its broad adaptability to a wide variety of farming systems is also noteworthy.4 Potatoes are an excellent source of complex carbohydrates ( 碳水化合物), which release their energy slowly, and have only 5 percent of wheat"s fat content. They contain only a quarter of the calories of bread and, according to the Potato Center, when boiled, potatoes have more protein and nearly twice the calcium (钙) as corn. Additionally, they are good sources of vitamin C, iron, potassium (钾) and zinc (锌).5 The Food and Agricultural Organization recently surveyed food price inflation in over 70 of the poor countries. Cereal price inflation was much higher and far more widespread than for potatoes. A significant factor behind the potato"s affordability is the fact that unlike other agricultural products, the potato is not yet a global commodity, and has therefore not attracted speculative investors. Raw potatoes are heavy and can rot during transit, so global trade has been slow to take off. Also, potatoes are susceptible (易受影响的) to infection with disease, hindering (阻碍) export. According to analysts" estimates, less than 5 percent of potatoes are traded internationally, with prices driven primarily by local tastes instead of international demand. Paragraph 4 ______
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Freezing to Death for BeautyPeople in Beijing wear a lot of clothing during winter to fend off (抵御) the cold. In the United States, however, people wear 1 , partly because the car is the primary mode of transportation. Cars take 2 straight to their workplaces, which are heated well. The American diet is full of calories, so their 3 can afford to burn heat more quickly.Fewer layers of clothing give people the opportunity to stay 4 . Lots of Yale girls wear skirts 5 when it"s 10 degrees Centigrade outside. Some of them at least wear boots, tights, and leg-warmers. Some, however, really just go for the look 6 the risk of health. These girls have no pants to prevent their 7 , and no socks to protect their feet. A mini skirt and a pair of stilettos (细高跟鞋) are all that they wear.Typically, the ones pursuing fashion are 8 , with little body fat. Just by the nature of their bodies, they are already at a disadvantage compared with normal people in 9 weather. I have always 10 , whenever I pass these girls, how they manage to refrain from shivering and just smile like spring had arrived.And then there are the guys. The girls can be said to 11 health for beauty. But why do guys 12 so little It is not like, once they take off some layers, they suddenly become better-looking. They are not exactly being fashionable when they 13 wear sporty (花哨的) shorts and shower slippers in the midst of winter. It"s not cute(喜人的).Of course, people have the freedom to look whatever 14 they want. I am just surprised that, given the vast difference between winter and summer temperatures in Connecticut, they can still 15 like they are partying on the beach in the middle of February.
Freezing to Death for BeautyPeople in Beijing wear a lot of clothing during winter to fend off (抵御) the cold. In the United States, however, people wear 1 , partly because the car is the primary mode of transportation. Cars take 2 straight to their workplaces, which are heated well. The American diet is full of calories, so their 3 can afford to burn heat more quickly.Fewer layers of clothing give people the opportunity to stay 4 . Lots of Yale girls wear skirts 5 when it"s 10 degrees Centigrade outside. Some of them at least wear boots, tights, and leg-warmers. Some, however, really just go for the look 6 the risk of health. These girls have no pants to prevent their 7 , and no socks to protect their feet. A mini skirt and a pair of stilettos (细高跟鞋) are all that they wear.Typically, the ones pursuing fashion are 8 , with little body fat. Just by the nature of their bodies, they are already at a disadvantage compared with normal people in 9 weather. I have always 10 , whenever I pass these girls, how they manage to refrain from shivering and just smile like spring had arrived.And then there are the guys. The girls can be said to 11 health for beauty. But why do guys 12 so little It is not like, once they take off some layers, they suddenly become better-looking. They are not exactly being fashionable when they 13 wear sporty (花哨的) shorts and shower slippers in the midst of winter. It"s not cute(喜人的).Of course, people have the freedom to look whatever 14 they want. I am just surprised that, given the vast difference between winter and summer temperatures in Connecticut, they can still 15 like they are partying on the beach in the middle of February.
Electric BackpackBackpacks are convenient. They can hold your books, your lunch, and a change of clothes, leaving your hands free to do other things. Someday, if you don"t mind carrying a heavy load, your backpacks might also power your MP3 player, keep your cell phone running, and maybe even light your way home.Lawrence C. Rome and his colleagues from the University of Pennsylvania in Philadelphia have invented a backpack that makes electricity from energy produced while its wearer walks. In military actions, search-and-rescue operations, and scientific field studies, people rely increasingly on cell phones, global positioning system (GPS) receivers (接收器), night-vision goggles (夜视镜), and other battery-powered devices to get around and do their work. The backpack"s electricity-generating feature could greatly reduce the amount of a wearer"s load now devoted to spare batteries.The backpack"s electricity-creating powers depend onspringsused to hang a cloth pack from its metal frame. The whole pack moves up and down as the person walks. A special mechanism converts movements of the pack to electricity, which can be as much as 7.4 watts.Unexpectedly, tests showed that wearers of the new backpack alter their gaits (步法) in response to the pack"s oscillations (摆动), so that they carry loads more comfortably and with less effort than they do ordinary backpacks. Because of that surprising advantage, Rome plans to commercialize both electric and nonelectric versions of the backpack.The backpack could be especially useful for soldiers, scientists, mountaineers (登山运动员), and emergency workers who typically carry heavy backpacks. For the rest of us, power-generating backpacks could make it possible to walk, play video games, watch TV, and listen to music, all at the same time. Electricity-generating packs aren"t on the market yet, but if you do get one eventually, just make sure to look both ways before crossing the street! The sentence "if you do get one eventually, just make sure to look both ways before crossing the street!" implies ______.
Freezing to Death for BeautyPeople in Beijing wear a lot of clothing during winter to fend off (抵御) the cold. In the United States, however, people wear 1 , partly because the car is the primary mode of transportation. Cars take 2 straight to their workplaces, which are heated well. The American diet is full of calories, so their 3 can afford to burn heat more quickly.Fewer layers of clothing give people the opportunity to stay 4 . Lots of Yale girls wear skirts 5 when it"s 10 degrees Centigrade outside. Some of them at least wear boots, tights, and leg-warmers. Some, however, really just go for the look 6 the risk of health. These girls have no pants to prevent their 7 , and no socks to protect their feet. A mini skirt and a pair of stilettos (细高跟鞋) are all that they wear.Typically, the ones pursuing fashion are 8 , with little body fat. Just by the nature of their bodies, they are already at a disadvantage compared with normal people in 9 weather. I have always 10 , whenever I pass these girls, how they manage to refrain from shivering and just smile like spring had arrived.And then there are the guys. The girls can be said to 11 health for beauty. But why do guys 12 so little It is not like, once they take off some layers, they suddenly become better-looking. They are not exactly being fashionable when they 13 wear sporty (花哨的) shorts and shower slippers in the midst of winter. It"s not cute(喜人的).Of course, people have the freedom to look whatever 14 they want. I am just surprised that, given the vast difference between winter and summer temperatures in Connecticut, they can still 15 like they are partying on the beach in the middle of February.
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