单选题When Marine Lt. Alan Zarracina finally did the splits after months of struggling with the difficult pose in yoga class, the limber women around him applauded. Zarracina, a 24-year-old Naval Academy graduate and flight student, admits he would have a hard time explaining the scene to other Marines. Each class ends with a chant for peace. Then, instructor Nancy La Nasa hands students incense sticks as a gift for their 90 minutes of back bends, shoulder stands and other challenging positions. Zarracina has tried to drag some of his military friends to class, but they make fun of hint. "It's not necessarily considered masculine,' he said. Still, the popular classes, based on ancient Hindu practices of meditation through controlled breathing, balancing and stretching, are catching on in military circles as a way to improve flexibility, balance and concentration. A former Navy SEAL told Zarracina about the class. The August edition of Fit Yoga, the nation's second-largest yoga magazine with a circulation of 100,000, features a photo of two Naval aviators doing yoga poses in full combat gear aboard an aircraft carrier. "At first it seemed a little shocking--soldiers practicing such a peaceful art," writes editor Rita Trieger. Upon closer inspection, she said, she noticed "a sense of inner calm' on the aviators' faces. "War is hell, and if yoga can help them find a little solace, that's good,' said Trieger, a longtime New York yoga instructor. Retired Adm. Tom Steffens, who spent34 years as a Navy SEAL and served as the director of the elite corps' training, regularly practices yoga at his home in Norfolk, Va. "Once in a while I'll sit in class, and everyone is a 20-something young lady with a 10-inch waist and here I am this old guy, ' he joked. Steffens, who said the stretching helped him eliminate the stiffness of a biceps injury after surgery, said the benefits of regular practice can be enormous. "The yoga cured all kinds of back pains," he said. "Being a SEAL, you beat up your body." Yoga breathing exercises can help SEALs with their diving, and learning to control the body by remaining in unusual positions can help members stay in confined spaces for long periods, he said. "The ability to stay focused on something, whether on breathing or on the yoga practice, and not be drawn off course, that has a lot of connection to the military," he said. "In our SEAL basic training, there are many things that are yoga-like in nature.

单选题 Until about four decades ago, crop yields in agricultural systems depended on{{U}} (1) {{/U}}resources, recycling organic matter, built-in biological control mechanisms and rainfall patterns. Agricultural yields were{{U}} (2) {{/U}}but stable. Production was{{U}} (3) {{/U}}by growing more than one crop or variety in space and time in a field as insurance against pest{{U}} (4) {{/U}}or severe weather. Inputs of nitrogen were{{U}} (5) {{/U}}by rotating major field crops with legumes. In turn, rotations suppressed insects, weeds and diseases by effectively{{U}} (6) {{/U}}the life cycles of these pests. A typical corn belt farmer grew corn{{U}} (7) {{/U}}with several crops including soybeans, and small grain production was intrinsic to maintain livestock. Most of the labor was done by the family with occasional hired help and no{{U}} (8) {{/U}}equipment or services were purchased from off4arm sources. In these type of farming systems the link between agriculture and ecology was quite{{U}} (9) {{/U}}and signs of environment degradation were seldom evident. But as agriculture modernization{{U}} (10) {{/U}}the ecology-farming linkage was often broken as ecological principles were{{U}} (11) {{/U}}. In fact, several agricultural scientists have arrived at a{{U}} (12) {{/U}}consensus that modem agriculture confronts an environment crisis. A growing number of people have become concerned about the long-term{{U}} (13) {{/U}}of existing food production systems. Evidence has shown that{{U}} (14) {{/U}}the present capital-and-technology-intensive fanning systems have been extremely productive and competitive, they also bring a{{U}} (15) {{/U}}of economic, environmental and social problems. Evidence also shows that the very nature of the agricultural structure and prevailing polices have led to this environmental{{U}} (16) {{/U}}by favoring large farm size, specialized production, crop monocultures and mechanization. Today as more and more farmers are integrated{{U}} (17) {{/U}}international economies, imperatives to{{U}} (18) {{/U}}disappear and monocultures are rewarded by economies of scale. In turn, lack of rotations and diversification{{U}} (19) {{/U}}key self-regulating mechanisms, turning monocultures into highly{{U}} (20) {{/U}}agro-ecosystems dependent on high chemical inputs.

单选题The author's tone is ______.

单选题We learn from the passage that an emotion is created by something ______.

单选题Which of the following would be the best title?______

单选题Whether a job can be classified as labor or work depends on______.

单选题According to the passage, when was the new planet first detected?

单选题Kevin Hines, a manic-depressive, was 19 and in one of his weekly downswings on an overcast Monday morning in 2000. He went to the nearby Golden Gate Bridge to kill himself mostly because, with only a four-foot (1.2-metre) railing to leap, "I figured it was the easiest way." He dived over, but flipped and hit the water at 75mph with his feet first. His legs were crushed, but he somehow stayed conscious and started paddling with his upper body until the Coast Guard fished him out. Mr. Hines is one of 26 people who have survived suicide attempts at the bridge, but 1 223 are known to have succeeded (i. e., were seen jumping or found floating). People are throwing themselves off the bridge at the rate of two a month, which makes it the most popular place in the world for suicides. One book on the subject says that the Golden Gate is "to suicide what Niagara Falls is to honeymooners". Many San Franciscans think that the solution is to emulate the Empire State Building, the Sydney Harbour Bridge, the Eiffel Tower, St. Peter's basilica and other such places and put up a simple barrier. This, however, is a decision for the 19 board members of the Golden Gate Bridge, Highway and Transportation District, an entity that oversees the bridge itself and the buses and ferries that operate in the area. Most of its revenues' come from tolls and fares, and the district loses money. A barrier would cost between $15 million and $ 25 million. So the Psychiatric Foundation of Northern California, which has adopted the barrier as its cause, considers it a success that the board has merely allowed a feasibility study, for which various private and public donors have raised $ 2 million. Mel Blaustein, a director at the foundation, has heard several arguments against a barrier over the years-too ugly, too expensive, and so forth--but the most persistent has been that people would simply kill themselves somewhere else, so why bother.'? This is nonsense, he says, "Most suicides are impulsive and preventable." A bridge without a barrier, adds Pat Hines, Kevin's father, is "like leaving a loaded gun in the psychiatric ward./

单选题The word "fallacy" (Line 3, Paragraph 1 ) most probably means

单选题Which of the following statements about the relationship between television and its viewers can best be inferred from the passage?

单选题It can be inferred from the text that American history textbooks used to assert that

单选题If you are rich and interested in new devices, you would

单选题Every second, 1 hectare of the world's rainforest is destroyed. That's equivalent to two football fields. An area the size of New York City is lost every day. In a year, that adds up to 31 million hectares—more than the land area of Poland. This alarming rate of destruction has serious consequences for the environment; scientists estimate, for example, that 137 species of plant, insect or animal become extinct every day due to logging. In British Columbia, where, since 1990, thirteen rainforest valleys have been clearcut, 142 species of salmon have already become extinct, and the habitats of grizzly bears, wolves and many other creatures are threatened. Logging, however, provides jobs, profits, taxes for the government and cheap products of all kinds for consumers, so the government is reluctant to restrict or control it. Much of Canada's forestry production goes towards making pulp and paper. According to the Canadian Pulp and Paper Association, Canada supplies 34% of the world's wood pulp and 49% of its newsprint paper. If these paper products could be produced in some other way, Canadian forests could be preserved. Recently, a possible alternative way of producing paper has been suggested by agriculturalists and environmentalists: a plant called hemp. Hemp has been cultivated by many cultures for thousands of years. It produces fiber which can be made into paper, fuel, oils, textiles, food, and rope. For many centuries, it was essential to the economies of many countries because it was used to make the ropes and cables used on sailing ships; colonial expansion and the establishment of a world wide trading network would not have been possible without hemp. Nowadays, ships' cables are usually made from wire or synthetic fibres, but scientists are now suggesting that the cultivation of hemp should be revived for the production of paper and pulp. According to its proponents, four times as much paper can be produced from land using hemp rather than trees, and many environmentalists believe that the large-scale cultivation of hemp could reduce the pressure on Canada's forests. However, there is a problem: hemp is illegal in many countries of the world, This plant, so useful for fiber, rope, oil, fuel and textiles, is a species of cannabis, related to the plant from which marijuana is produced. In the late 1930s, a movement to ban the drug marijuana began to gather force, resulting in the eventual banning of the cultivation not only of the plant used to produce the drug, but also of the commercial fiber-producing hemp plant. Although both George Washington and Thomas Jefferson grew hemp in large quantities on their own land, any American growing the plant today would soon find himself in prison—despite the fact that marijuana cannot be produced from the hemp plant, since it contains almost no THC (the active ingredient in the drug). In recent years, two major movements for legalization have been gathering strength. One group of activists believes that ALL cannabis should be legal—both the hemp plant and the marijuana plant—and that the use of the drug marijuana should not be an offense. They argue that marijuana is not dangerous or addictive, and that it is used by large numbers of people who are not criminals but productive members of society. They also point out that marijuana is less toxic than alcohol or tobacco. The other legalization movement is concerned only with the hemp plant used to produce fiber; this group wants to make it legal to cultivate the plant and sell the fiber for paper and pulp production. This second group has had a major triumph recently: in 1997, Canada legalized the farming of hemp for fiber. For the first time since 1938, hundreds of farmers are planting this crop, and soon we can expect to see pulp and paper produced from this new source.

单选题Nearly three-quarter of the Earth is covered with water. The (1) of the continents, especially in the temperate zones, is very much (2) by the oceans around them. The areas (3) the sea have a " (4) climate", with rather cool summers and warm winters. The interiors, far from the sea, have a climate with extremely hot summers and cold winters. Rain comes from the evaporation of rivers, seas and lakes. (5) after heavy rain, the pavements in a city do not take (6) to dry because the rainwater evaporates into the air. On a warm dry day it evaporates very rapidly, as warm air can absorb more (7) than cold air. (8) at any particular temperature, the atmosphere can hold only a certain (9) amount of water vapor. The air is then saturated, (10) a sponge that cannot hold any more water. The lower the temperature, the (11) water vapour is required to saturate the air. All over the surface of the Earth, millions of tons of water are evaporating every second, (12) in the air into drops so small that it (13) thousands of them to make a single raindrop. It is these (14) droplets that make clouds. When clouds roll in from the sea over the warmer land, they are forced to (15) and become cooler in the colder upper atmosphere. As the air (16) it may pass through its (17) point and then some of its water vapor turns to rain. Day in, day out, the (18) water circulates between the air and the land: rivers evaporate to make clouds, clouds make rain, rain makes rivers which (19) run into the sea. This is called the rain (20) .