单选题This text is too difficult to comprehend .

单选题American scientists predicted that Mount Saint Helens was to erupt soon.

单选题She cried aloud {{U}}all at once{{/U}}. A. for a long time B. suddenly C. for no reason D. quickly

单选题 阅读下面这篇短文，短文后列出7个句子，请根据短文的内容对每个句子做出判断。 {{B}}The Ice Age{{/B}} Twenty thousand years ago, the earth was held in control by relentlessly (不宽容地) probing fingers of ice that drew power from frigid strongholds in the north and crept southwestward to bury forests, fields, and mountains. Landscapes that were violated by the slowly moving glaciers(冰川 )would carry the scars of this advance far into the future. Temperatures dropped deeply, and land surfaces in many parts of the world were depressed by the unrelenting weight of the thrusting ice. At the same time, so much was drawn from the oceans to form these huge glaciers that sea levels around the world fell by three hundred and fifty feet, and large areas of the continental shelf became dry land. This period of the Earth's history had come to be called the Ice Age. In all, about eleven million square miles of land were covered with ice. The Ice Age terminated about fourteen thousand years ago when the ice sheets began to retreat. It took about seven thousand years for the ice to retreat to its present level.

单选题Dark Forces Dominate Universe The earth, moon, sun and all visible stars in the sky make up less than one percent of the universe. Almost all the rest is dark matter and dark energy, unknown forces that 1 astronomers. Observations in recent years have changed the basic 2 of how the universe evolved and have indicated how little is known about the major forces and substances that 3 our world. Astronomers now know that luminous (发光的) matter—stars, planets and hot gas—accounts 4 only about 0.4 percent of the universe. Non-luminous components, such as black holes and intergalactic (星间的) gas, 5 up 3.6 percent. The rest is either dark matter, about 23 percent, or dark energy, about 73 percent. Dark matter, sometimes 6 "cold dark matter", has been known for some time. Only recently have researchers come to understand the key role it 7 in the formation of stars, planets and even people. "We 8 our very existence to dark matter," said physicist Paul Steinhardt and a co-author of a review on dark matter which 9 not long ago in the journal Science. "Dark matter dominated the structure 10 in the early universe," Steinhardt said. "For the first few billion years dark matter contained most of the mass of the universe. You can think of ordinary matter 11 a froth (泡沫) of an ocean of dark matter. The dark matter dumps (结成块) and the ordinary matter falls into it. That 12 to the formation of the stars and galaxies (星系)." Without dark matter, there would be virtually no structures in the universe. The nature of dark matter is 13 . It cannot be seen or detected directly. Astronomers know it is there because of its 14 on celestial (天体的) objects that can be seen and measured. But the most dominating force of all in the universe is called dark energy, a recently 15 power that astronomers say is causing the galaxies in the universe to separate at a faster and faster speed.

单选题Manufacturers spend millions of dollars on advertising to {{U}}entice{{/U}} people to buy their products.

单选题He Was rather {{U}}vague{{/U}} about the reasons why he never finished school．

单选题Please give my best wishes to your family.

单选题The Railway Labor Mediation Act of 1926 supported the use of collective bargaining to {{U}}avert{{/U}} interruption of rail service.

单选题There is a small risk of brain damage from such an operation.

单选题You will be eligible to vote next year. A. competent B. possible C. enough D. allowed

单选题His claims seem credible to many people.

单选题It is very difficult for a child to {{U}}adhere to{{/U}} rules. A. follow B. remember C. understand D. learn

单选题It doesn't {{U}}stand to reason{{/U}} that he would lie,

单选题{{B}}第二篇{{/B}} Male and Female Pilots Cause Accidents Differently Male pilots flying general aviation (private) aircraft in the United States are more likely to crash due to inattention or flawed decision making. While female pilots are more likely to crash from mishandling (错误地处理) the aircraft (航行器). These are the results of a study by researchers at the Johns Hopkins University Bloomberg School of Public Health. The study identifies the differences between male and female pilots in terms of circumstances of the crash and the type of pilots error involved. "Crashes of general aviation aircraft account for 85 percent of all aviation deaths" in the United States. The crash rate for male pilots as for motor vehicle drivers, exceeds that of crashes of female pilots, " explains Susan P. Baker, MPH, professor of health policy and management at the Bloomberg School of Public Health. "Because pilot youth and inexperience are established contributors to aviation crashes, we focused on only mature pilots, to determine the gender differences in the reasons for the crash. The researchers extracted data for this study from a large research project on pilot aging and flight safety. The data were gathered from general aviation (航行) crashes of airplanes and helicopters between 1983 and 1997, involving 144 female pilots and 267 male pilots aged 40--63. Female pilots were matched with male pilots in a 1:2 ratio, by age, classes of medical and pilot certificates, state or area of crash, and year of crash. Then the circumstances of the crashes and the pilot error involved were categorized and coded without knowledge of pilot gender. The researchers found that loss of control on landing or takeoff was the most common circumstance for both sexes, leading to 59 percent of female pilots' crashes and 36 percent of males'. Experiencing mechanical failure, running out of fuel (燃料), and landing the plane with the landing gear up were among the factors more likely with males, while stalling was more likely with females. The majority of the crashes -- 95 percent for females and 88 percent for males -- involved at least one type of pilot error. Mishandling aircraft kinetics was the most common error for both sexes, but was more common among females (accounting for 81 percent of the crashes) than males (accounting for 48 percent). Males, however, appeared more likely to be guilty of poor decision-making, risk-taking, and inattentiveness, examples of which include misjudging weather and visibility or flying an aircraft with a known defect (过失). Females, though more likely to mishandle or lose control of the aircraft, were generally more careful than their male counterparts.

单选题There are various ways to solve the problem.A. sameB. ninnyC. helpfulD. different

单选题A gift to the United States from France, the Statue of Liberty was {{U}}assembled{{/U}} and dedicated in 1886.

单选题Undoubtedly, ______ wins the election is going to have a tough job geeing the economy back on its feet.A. anyoneB. whoC. whoeverD. everyone

单选题Hospital Mistreatment According to a study, most medical interns report experiencing mistreatment, including humiliation by senior doctors, 1 threatened, or physical abuse in their first year out of medical school. The findings come from analysis of the 2 a 13-page survey mailed in January 1991 to 1,733 second-year residents. The survey and 3 appear in the April 15th issue of the Journal of the American Medical Association. Overall, out of the 1,277 residents 4 completed surveys, 1,185 said that they had experienced at least one incident of mistreatment in their intern year. 5 reporting incidents where they were abused, more than 45% of the residents said they had witnessed at least one incident where other persons 6 false medical records. Moreover, nearly three quarters of the residents said they had witnessed mistreatment of patents by other residents, attending physicians, or nurses. Almost 40% said patient mistreatment was a frequent 7 More than 10% of the residents said they experenced some type of sexual harassment or discrimination, verbal abuse was the most common problem cited. When abusive incidents were limited to events occurring three or more times, 53% of the respondents reported that they 8 belittled or humiliated by more senior residents, while just over 21% reported someone taking credit for their work. Being " 9 tasks for punishment," "being pushed, kicked or hit," and 10 someone "threatening your reputation or career," were reported as a more 11 occurrence by over 10% of the responding residents.

单选题Jean has {{U}}made up her mind{{/U}} not to go to the meeting. A. tried B. promised C. decided D. attempted