单选题In a supermarket, all commodities are open to customers who can select what they need ______.

单选题Many people like the color white as it is a ______ of purity.

单选题Such changes, A combined with the erosion of B the area's barrier islands, and the Bush administration's policy of C opening up more wetlands to development, weakened the natural frontline defense against a hurricane storm surge D and leave the city more vulnerable to death and destruction.

单选题The Chinese Red Cross______ a generous sum to the relief fund for the physically disabled.

单选题Thelastparagraphshowsthattheauthor‘sattitudetowardsthereliabilityofnewtechniquesis

单选题 Assuming that a constant travel-time budget, geographic constraints and short-term infrastructure constraints persist as fundamental features of global mobility, what long-term results can one expect? In high-income regions, {{U}}(41) {{/U}} North America, our picture suggests that the share of traffic {{U}}(42) {{/U}} supplied by buses and automobiles will decline as high-speed transport rises sharply. In developing countries, we {{U}}(43) {{/U}} the strongest increase to be in the shares first for buses and later for automobiles. Globally, these {{U}}(44) {{/U}} in bus and automobile transport are partially offsetting. In all regions, the share of lowspeed mil transport will probably continue its strongly {{U}}(45) {{/U}} decline. We expect that throughout the period 1990～2050, the {{U}}(46) {{/U}} North American will continue to devote most of his or her 1.1-hour travel-time {{U}}(47) {{/U}} to automobile travel. The very large demand {{U}}(48) {{/U}} air travel (or high-speed mil travel) that will be manifest in 2050 {{U}}(49) {{/U}} to only 12 minutes per person a day; a little time goes a long way in the air. In several developing regions, most travel {{U}}(50) {{/U}} in 2050 will still be devoted to nonmotorized modes. Buses will persist {{U}}(51) {{/U}} the primary form of motorized transportation in developing countries for decades.{{U}} (52) {{/U}} important air travel becomes, buses, automobiles and {{U}}(53) {{/U}} lowspeed trains will surely go on serving vital functions.{{U}} (54) {{/U}} of the super-rich already commute and shop in aircraft, but average people will continue to spend most of their travel time on the {{U}}(55) {{/U}}.

单选题In the week before Christmas, shoppers ______ the stores.

单选题To paraphrase the noted eighteenth-century scholar, Samuel Johnson, despite all the refinements of subtlety and the dogmatism of learning, it is by the common sense and compassion of readers that are uncorrupted by the prejudices of some opinionated scholars who the characters and situations in medieval and Elizabethan literature, as in any other literature, can best be judged. A. despite B. that C. who D. as

单选题A(A noisy) B(aggressive) cousin of the crow, the magpie has C(those) bird's thievish D(habits).

单选题People who feel miserable with computers are those ______.

单选题Being out of employment, they have to Ulounge/U at street corners and wait for a chance to get a job.

单选题The geology of the Earth's surface is dominated by the particular properties of water. Present on Earth in solid, liquid, and gaseous states, water is exceptionally reactive. It dissolves, transports, and precipitates many chemical compounds and is constantly modifying the face of the Earth. Evaporated from the oceans, water vapor forms clouds, some of which are transported by wind over the continents. Condensation from the clouds provides the essential agent of continental erosion: rain. Precipitated onto the ground, the water trickles down to form brooks, streams, and rivers, constituting what is called the hydrographic network. This immense polarized network channels the water toward a single receptacle: an ocean. Gravity dominates this entire step in the cycle because water tends to minimize its potential energy by running from high altitudes toward the reference point that is sea level. The rate at which a molecule of water passes through the cycle is not random but is a measure of the relative size of the various reservoirs. If we define residence time as the average time for a water molecule to pass through one of the three reservoirs—atmosphere, continent, and ocean—we see that the times are very different. A water molecule stays, on an average, eleven days in the atmosphere, one hundred years on a continent and forty thousand years in the ocean. This last figure shows the importance of the ocean as the principal reservoir of the hydrosphere but also the rapidity of water transport on the continents. A vast chemical separation process takes places during the flow of water over the continents. Soluble ions such as calcium, sodium, potassium, and some magnesium are dissolved and transported. Insoluble ions such as aluminum, iron, and silicon stay where they are and form the thin, fertile skin of soil on which vegetation can grow. Sometimes soils are destroyed and transported mechanically during flooding. The erosion of the continents thus results from two closely linked and interdependent processes, chemical erosion and mechanical erosion. Their respective interactions and efficiency depend on different factors.

单选题The lady who has ______ for a night in the dead of the winter later turned out to be a distant relation of his.

单选题______telephone service provides immediate access to related personnel, which is free of charge.

单选题What would be the proper title for this passage?

单选题"Dimpy", as her friends call her, heard about the hazards of smoking in health class. "They showed pictures of lungs of people who smoked. It was gross," says the petite 14year-old. Yet, as she shops along the Third Street Promenade in Santa Monica, Calif. , the ninth grader points out all the places where she regularly buys cigarettes without hassle. "All my friends smoke," She shrugs, explaining the habit she developed in the sixth grade. "Once they pressure you, you start. And it's kind of hard to stop. " As the cigarette industry draws increasing fire, teen smokers like Dimpy are becoming the focus of concerned policy makers around the country. Supported by a University of Michigan study showing a dramatic rise in adolescent tobacco use, the White House is considering ways to curb the surge. Among the options: eliminating cigarette vending machines, restricting tobacco advertising, increasing the federal excise tax on cigarettes and launching a national media campaign directed at adolescents. A grand jury in New York has begun an investigation to determine whether Philip Moms Cos. concealed information linking nicotine levels and addictiveness. And the Justice Department is looking into whether tobacco company executives committed perjury in their April 1994 congressional testimony on how smoking affects health. Lack of credibility. But it's tough to get an antismoking message through to teens. The California Department of Health Service spends $12 million a year placing antismoking commercials on television, including popular MTV programs, but many teenagers aren't buying the message. Says Erica leona, who will enter eighth grade in the fall, "I don't think those ads work, because It's like a cartoon, it's too exaggerated. " In fact, teens seem skeptical about the potential effectiveness of any organized efforts to reduce smoking, like increasing taxes. While research shows that every time taxes go up, sales go down, including among teens, young people say the cost is relatively low in comparison with other vices. "You want weed, it'll cost you," says Robert Caldwell, 14. "For cigarettes, you just go anywhere, put 12 quarters into one of those machines, take it and go. " Other teens maintain that eliminating vending machines won't make cigarettes any harder to buy. "You give a guy enough to buy you a pack and a beer, and he'll buy the pack," says Cameron Davis, 13. And advertising isn't really what entices adolescents to smoke. For the most part, they say, teens smoke because of peer pressure. "It's like sex. " says 13-year-old Frances, who started smoking at age 9. "You feel like, if you don't do it with your boyfriend, he won't like you. " In addition, messages that relate to health don't compute with adolescents, who often feel invincible. It doesn't help, says Roxanne Cannon, editorial director of Teen and Sassy magazines, that so many teen idols such as Ethan Hawke, Jason Priestley and Luke Perry are seen smoking. Teens say any message is more effective if it's communicated by other kids. But even a White House appeal made by Chelsea Clinton might not get through to adolescents eager to smoke. "I don't listen to my mom when she tells me to stop," says Dimpy. "Why would I listen to anyone else. /

单选题The writer's message is that the built environment should be ______.

单选题We must try our best to lower the cost of our products. Otherwise the high cost will______our profit.