单选题It is the movement, not the color, of objects that excites the bull.

单选题"Salty" Rice Plant Boosts Harvests British scientists are breeding a new generation of rice plants that will be able to grow in soil containing salt water. Their work may enable abandoned farms to become productive once more. Tim Flowers and Tony Yeo, from Sussex University"s School of Biological Sciences, have spent several years researching how crops, such as rice, could be made to grow in water that has become salty. The pair have recently begun a three-year programme, funded by the Biotechnology and Biological Sciences Research Council, to establish which genes enable some plants to survive salty conditions. The aim is to breed this capability into crops, starting with rice. It is estimated that each year more than 10m hectares (公顷) of agricultural land are lost because salt gets into the soil and stunts (妨碍生长) plants. The problem is caused by several factors. In the tropics, mangroves (红树林) that create swamps (沼泽) and traditionally formed barriers to sea water have been cut down. In the Mediterranean, a series of droughts have caused the water table to drop, allowing sea water to seep (渗透) in Latin America, irrigation often causes problems when water is evaporated (蒸发) by the heat, leaving salt deposits behind. Excess salt then enters the plants and prevents them functioning normally. Heavy concentrations of minerals in the plants stop them drawing up the water they need to survive. To overcome these problems, Flowers and Yeo decided to breed rice plants that take in very little salt and store what they do absorb in cells that do not affect the plants" growth. They have started to breed these characteristics into a new rice crop, but it will take about eight harvests before the resulting seeds are ready to be considered for commercial use. Once the characteristics for surviving salty soil are known, Flowers and Yeo will try to breed the appropriate genes into all manners of crops and plants. Land that has been abandoned to nature will then be able to bloom again, providing much needed food in the poorer countries of the world.

单选题The policeman wrote down all the particulars of the accident. A．secrets B．details C．benefits D．words

单选题Before herbs were {{U}}available{{/U}} in supermarkets year-round, herb vinegar was made in the fall.

单选题You have to be patient if you want to sustain your position.

单选题{{B}}第三篇{{/B}} {{B}} Mysterious Nazca Drawings{{/B}} One of the most mysterious archaeological spectacles in the world is the immense complex of geometrical symbols, giant ground-drawings of birds and animals, and hundreds of long, ruler-straight lines, some right across mountains, which stretch over 1,200 square miles of the Peruvian tablelands, at Nazca. Nazca was first revealed to modern eyes in 1926 when three explorers looked down on the desert from a hillside at dusk and briefly saw a Nazca line highlighted by the rays of the sun. But it was not until the Peruvian airforce took aerial photographs in the 1940s that the full magnificence of the panorama was apparent. Hundreds of what looked like landing strips for aircraft were revealed. There were eighteen bird-like drawings, up to 400 feet long, four-sided figures with two lines parallel; and long needle-like triangles which ran for miles. Among the many abstract patterns were a giant spider, a monkey, a shark, all drawn on the ground on a huge scale. The scale is monumental, but from the ground almost invisible and totally incomprehensible. The amazing fact about Nazca, created more than 1,500 years ago, is that it can only be appreciated if seen from the air. Many, therefore, regarded it as a prehistoric landing ground for visitors from outer space, but Jim Woodman, an American explorer, who was long fascinated by the mystery of Nazea, had a different opinion. He believed that Nazca only made sense if the people who had designed and made these vast drawings on the ground could actually see them, and that led him to the theory that the ancient Peruvians had somehow learned to fly, as only from above could they really see the extent of their handiwork. With this theory in mind, he researched into ancient Peruvian legends about flight and came to the conclusion that the only feasible answer was a hot-air balloon. To prove his theory, Woodman would have to make such a thing using the same fabrics and fibers that would have been available to the men of Nazca at the time. He started by gathering information from ancient paintings, legends, books and archaeological sites. After many attempts, Woodman built a balloon-type airship. It took him into the air, letting him have the sensation he had never had from viewing the same ground that he had seen many times. His flight was a modern demonstration of an ancient possibility.

单选题{{U}}Enormous{{/U}} sums of money have been spent on space exploration. A. Much B. Large C. Small D. Fixed

单选题The rules are too rigid to allow for human error.

单选题The girl practiced Uceaselessly /Uto become a professional pianist.

单选题My mother has lived {{U}}separately{{/U}} since my father died 20 years ago.

单选题The Smog For over a month, Indonesia was in crisis. Forest fires raged out of control as the country suffered its worst drought for 50 years. Smoke from the fires mixed with sunlight and hot dry air to form a cloud of smog. This pollution quickly spread and within days it was hanging over neighboring countries including Malaysia, Singapore and Thailand. When the smoke combined with pollution from factories and cars, it soon became poisonous. Dangerous amounts of CO became trapped under the smog and pollution levels rose. People wheezed (喘息) and coughed as they left the house and their eyes watered immediately. The smog made it impossible to see across streets and whole cities disappeared as grey soot (烟灰) covered everything. In some areas, water was hosed (用胶管浇) from high-rise city buildings to try and break up the smog. Finally, heavy rains, which came in November. Put out the fires and clear the air. But the environmental costs and health problems will remain. Many people from South-Eastern Asian cities already suffer from breathing huge amounts of car exhaust fumes and factory pollution Breathing problems could well increase and many non-sufferers may have difficulties for the first time. Wildlife has suffered too. In lowland forests, elephants, deer, and tigers have been driven out of their homes by smog. But smog is not just an Asian problem. In fact .was world was first used in London in 1905 to describe the mixture of smoke and thick fog. Fog often hung over the capital. Sometimes the smog was so thick and poisonous that people were killed by breathing problems or in accidents. About 4,000 Londoners died within five days as a result of thick smog in 1952.

单选题It is no use debating the relative merits of this policy.

单选题The two banks have announced plans to merge next year.

单选题The scientists began to {{U}}accumulate{{/U}} a huge mass of data. A. amass B. put up C. make up D. clear up

单选题She was grateful to him for being so good to her.

单选题Their business was successful as they now had a Ucompatible/U board of directors.

单选题It"s prudent to start any exercise program gradually at first.

单选题The passage implies that the writer and her boyfriend live in

单选题Global warming would have a devastating impact on low, lying island.

单选题UPractically/U all species of animals communicate either through sounds or through a large repertory of soundless codes.