单选题Migrant Workers In the past twenty years, there has been an increasing tendency for workers to move from one country to another. (1) some newly independent countries have understandably restricted most jobs to local people, others have attracted and welcomed migrant workers. This is particularly the case in the Middle East, (2) increased oil incomes have enabled many countries to (3) outsiders to improve local facilities. (4) the Middle East has attracted oil-workers from the USA and Europe. It has brought in construction workers and technicians from many countries, (5) South Korea and Japan. In view of the difficult living and working conditions in the Middle East, it is not (6) that the pay is high to attract suitable workers. Many engineers and technicians can earn at least (7) money in the Middle East as they can in their own country, and this is a major attraction. An allied benefit is the low taxation or complete lack of it. This increases the net amount of pay received by visiting workers and is very popular with them. Sometimes a disadvantage has a compensating advantage. (8) , the difficult living conditions often lead to increased friendship when workers have to depend on each other (9) safety and comfort. (10) , many migrant workers can save large sums of money partly (11) the lack of entertainment facilities. The work is often complex and full of problems but this merely presents greater challenge to engineers who prefer to find solutions (12) problems rather than do routine work in their home country. One major problem which (13) migrant workers in the Middle East is that their jobs are temporary ones. They are nearly always on contract, so it is not easy for them to plan ahead with great confidence. This is to be expected since no country welcomes a large number of foreign workers as permanent residents. (14) , migrant workers accept this disadvantage, along with others, because of the (15) financial benefits which they receive.

单选题People who care for those most vulnerable to the influenza infection needn't get flu shots.

单选题The same principles of education, prevention and early treatment can apply to mental health as well. One in 20 Americans over age 12 reported feeling depressed in 2006, with non -Hispanic blacks making up the largest percentage. Although 80% of Americans admitted that their symptoms interfered with their ability to work, only 29% had contacted a mental - health professional. Recent improvements in screening at primary -care facilities, one of the goals set by Healthy People 2010, may help address this problem: while 62% of primary - care facilitiesprovided treatment for mental disorders in 2000, 74% do so now. Which of the following is true?A. 74% of primary - care facilities provided treatment for mental disorders in 2006.B. 5% Americans over age 12 said they felt depressed in 2006.C. 80% of Americans with mental problems consulted mental--health professionals.D. 29% of Americans reported interference of their symptoms with their work.

单选题Her faith upheld her in times of sadness. A. excited B. supported C. inspired D. directed

单选题 Sleep Lets Brain File Memories To sleep. Perchance to file? Findings published online this week by the Proceedings of the National Academy of Sciences further support the theory that the brain organizes and stows memories formed during the day while the rest of the body is catching zzz's. Gyorgy Buzsaki of Rutgers University and his colleagues analyzed the brain waves of sleeping rats and mice. Specifically, they examined the electrical activity emanating from the somatosensory neocortex (an area that processes sensory information) and the hippocampus, which is a center for learning and memory. The scientists found that oscillations in brain waves from the two regions appear to be intertwined. So-called sleep spindles (bursts of activity from the neocortex) were followed tens of milliseconds later by beats in the hippocampus known as ripples. The team posits that this interplay between the two brain regions is a key step in memory consolidation. A second study, also published online this week by the Proceedings of the National Academy of Sciences, links age-associated memory decline to high glucose levels. Previous research had shown that individuals with diabetes suffer from increased memory problems. In the new work, Antonio Convit of New York University School of Medicine and his collaborators studied 30 people whose average age was 69 to investigate whether sugar levels, which tend to increase with age, affect memory in healthy people as well. The scientists administered recall tests, brain scans and glucose tolerance tests, which measure how quickly sugar is absorbed from the blood by the body's tissues. Subjects with the poorest memory recollection, the team discovered, also displayed the poorest glucose tolerance. In addition, their brain scans showed more hippocampus shrinkage than those of subjects better able to absorb blood sugar. "Our study suggests that this impairment may contribute to the memory deficits that occur as people age," Convit says. "And it raises the intriguing possibility that improving glucose tolerance could reverse some age-associated problems in cognition." Exercise and weight control can help keep glucose levels in check, so there may be one more reason to go to the gym.

单选题That mysterious island has always fascinated me.

单选题His motive for working hard is that he needs money.A. motivationB. activeC. motionD. nature

单选题Ulcers Even though ulcers appear to run in families, lifestyle plays more of a role than genetic factors in causing the illness, according to a report in the April 13th Journal of Internal Medicine . In particular, smoking and stress in men and the regular use of pain-releasing medicines in women were linked with an increased risk of developing an ulcer. Overall, 61% of ulcer risk appears to be due to environmental factors, such as smoking, and the remaining 39% is due to genes according to Dr.Ismo Raiha of the University of Turky and colleagues at the University of Helsinki, Finland. Some researchers had suggested that families may spread Helicobacteria pylori, the bacteria that can cause ulcers. However, the new study suggests this is unlikely, according to the report. Raiha and colleagues studied data from more than 13,000 pairs of twins "to examine the roles of genetic and environmental factors in the origin of peptic ulcer disease," they explain. Both twins were more likely to develop an ulcer if the pair were genetically the same as compared with a pair of fraternal twins, suggesting that there must be some genetic susceptibility to ulcer development. However, the risk was no greater in twins living together compared with twins living apart, suggesting that shared exposure to H. pylori was not to blame. "Environment effects were not due to factors shared by family members, and they were related to smoking and stress in men and the use of analgesics in women," the authors wrote. "The minor effects of shared environment to disease liability do not support the concept that the grouping of risk factors, such as H. pylori infection, would explain the genetic factor of peptic ulcer disease," they concluded.

单选题{{U}}Practically{{/U}} all animals communicate through sounds

单选题Cosmetic surgery is more popular in the US than anywhere else.

单选题Foreign money can be {{U}}converted{{/U}} into the local currency at this bank,

单选题Living Standards The differences in living standards around the world are vast. In 1993, the average American had an income of about $25,000. In the same year, the average Mexican earned $7,000, and the average Nigerian earned $1,500. Not surprisingly, this large variation in average income is reflected in various measures of the quality of life. Changes in living standards over time are also large. In the United States, incomes have historically grown about 2 percent per year (after adjusting for changes in the cost of living). At this rate, average income doubles every 35 years. In some countries, economic growth has been even more rapid. In Japan, for instance, average income has doubled in the past 20 years, and in South Korea it has doubled in the past 10 years. What explains these large differences in living standards among countries and over time? The answer is surprisingly simple. Almost all variation in living standards is attributable to differences in countries' productivity--that is, the amount of goods and services produced from each hour of a worker's time. In nations where workers can produce a large quantity of goods and services per unit of time, most people enjoy a high standard of living; in nations where workers are less productive, most people must endure a more meager existence. Similarly, the growth rate of a nation's productivity determines the growth rate of its average income. The fundamental relationship between productivity and living standards is simple, but its implications are far-reaching. If productivity is the primary determinant of living standards, other explanations must be of secondary importance. For example, people might think that labor unions or minimum-wage laws contributed to the rise in living standards of American workers over the past century. Yet the real hero of American workers is their rising productivity. The relationship between productivity and living standards also has great implications for public policy. When thinking about how any policy will affect living standards, the key question is how it will affect our ability to produce goods and services. To improve living standards, policymakers need to raise productivity by ensuring that workers are well educated, have the tools needed to produce goods and services, and have access to the best available technology.

单选题The book shows only a superficial understanding of the historical context.

单选题They soon began to {{U}}investigate{{/U}} the cause of the fire.

单选题The college offers courses in a variety of Utrades/U.

单选题Anderson left the table, remarking that he had some work to do.

单选题She read a poem which depicts the splendor of the sunset.

单选题He could not tolerate the extremes of heat in the desert.

单选题The President made a brief visit to Beijing.

单选题He is certain that the dictionary is just what I want.