单选题Most nurses are women, but in the higher ranks of the medical profession women are in a small number .

单选题The fuel tanks had a capacity of 140 liters.

单选题下面有3篇短文，每篇短文后有5道题，每道题后面有4个选项。请仔细阅读短文并根据短文回答其后面的问题，从4个选项中选择1个最佳答案。{{B}}第一篇{{/B}} Two People, Two Paths You must be familiar with the situation: dad's driving, mum's telling him where to go. He's sure that they need to turn left. But she says it's not for another two blocks. Who has the better sense of direction.'? Men or women? They both do, a new study says, but in different ways. Men and women, Canadian researchers have found, have different methods of finding their way. Men look quickly at landmarks (地标) and head off in what they think is the right direction. Women, however, try to picture the whole route in detail and then follow the path in their head. "Women tend to be more detailed. "said Edward Cornell, who led the study "While men tend to be a little bit faster and a little bit more intuitive(直觉感知的). " In fact, said Cornell, "sense of direction" isn't one skill but two. The first is the "survey method". This is when you see an area from above, such as a printed map. You can see, for example, where the hospital is, where the church is and that the supermarket is on its right. The second skill is the "route method". This is when you use a series of directions. Yon start from the hospital, then turn left, turn right, go uphill, and then you see the supermarket. Men are more likely to use the survey method while women are more likely to use one route and follow directions. Both work and neither is better. Some scientists insist that these different skills have a long history. They argue it is because of the difference in traditional roles. In ancient times, young men often went far away with the older men to fish or hunt. The trip took hours or days and covered unfamiliar places. The only way to know where you were was to use the survey method to remember landmarks—the mountains, the lakes and so on. The women, on the other hand, took young girls out to find fruits and plants. These activities were much closer to home but required learning well-used paths. So, women's sense of space was based on learning certain routes.

单选题Manufacturers report a big drop in new orders.

单选题Life Expectancy in the Last Hundred Years A hundred years ago, life expectancy in developed countries was about 47; in the early 21st century, men in the United States and the United Kingdom can expect to live to about 74. Women to about 80, and these 1 are rising all the time. What has brought 2 these changes? When we look at the life 3 of people 100 years ago, we need to look at the greatest 4 of the time. In the early 20th century, these were the acute and often 5 infectious diseases such as smallpox. Many children died very young from these diseases and others, and the weak and elderly were always at risk. In the 6 world these diseases are far 7 today, and in some cases have almost disappeared. A number of 8 have led to this: improvements in sanitation and hygiene, the discovery and use of antibiotics, which 9 bacterial diseases much less dangerous, and vaccinations 10 common diseases. 11 , people"s general health has improved with improvements in our general environment: cleaner air, better means of preserving food, better and warmer housing, and better understanding of nutrition. Genetically, we should all be able to live to about 85 but 12 people do live longer today, there are still some big killers around that are preventing us from consistently reaching that age. The problems that affect people today are the more chronic illnesses, such as heart disease and strokes, and those 13 by viruses, such as influenza and AIDS. Of course, cancer is a huge killer as well. In most cases these diseases affect 14 people, but there are worrying trends in the developed world with problems such as obesity 15 more heart disease and illnesses such as diabetes at younger ages. The killers today can be classed as "lifestyle diseases", which means that it may be possible to halt their progress.

单选题The nucleus of the atom is composed of swiftly moving protons and neutrons that are held together by very strong forces.

单选题The police tried in vain to break up the protest crowds in front of the government building.

单选题Our examination has been postponed until next Friday.A. put onB. put downC. put offD. put in

单选题If headaches only Uoccur/U at night, lack of fresh air is often the cause.

单选题Customers often {{U}}defer{{/U}} payment for as long as possible.

单选题Marvelous Metamaterials Invisibility cloaks would have remained impossible, forever locked in science fiction, had it not been for the development of metamaterials. In Greek, "meta" means beyond, and metamaterials can do things beyond what we see in the natural world-like shuffle light waves around an object, and then bring' them back together. If scientists ever manage to build a full-fledged invisibility cloak, it will probably be made of metamaterials. "We are creating materials that don't exist in nature, and that have a physical phenomenon that doesn't exist in nature," says engineer Dentcho Genov. "That is the most exciting thing." Genov designs and builds metamaterials such as those used in cloaking at Louisiana Tech University in Ruston, Louisiana. An invisibility cloak will probably not be the first major accomplishment to come from the field of metamaterials. Other applications are just as exciting. In many labs, for example, scientists are working on building a hyperlens. A lens is a device, usually made of glass that can change the direction of light waves. Lenses are used in microscopes and cameras to focus light, thus allowing a researcher to see small things or a photographer to capture image of things that are far away. A hyperlens, however, would be made of metamaterials. And since metamaterials can do things with light that ordinary materials can't, the hyperlens would be a powerful too 1. A hyperlens would allow researchers to see things at the smallest scale imaginable, as small as the wavelength of visible light. Genov points out that the science of metamaterials is driven by the imagination. If someone can think of an idea for a new behavior for fight, then the engineers can find a way to design a device using metamaterials. "We need people who can imagine," he says. Since 2006, many laboratories have been exploring other kinds of metamaterials that don't involve just visible light. In fact, scientists are finding that almost any kind of wave may respond to metamaterials. At the Polytechnic University of Valencia in Spain, Jose Sanchez-Dehesa is working with acoustics, or the science of sound. Just as an invisibility cloak shuffles waves of light, an "acoustic" cloak would shuffle waves of sound in a way that's not found in nature. In an orchestra hall, for example, an acoustic cloak could redirect the sound waves so someone sitting behind a column would hear the same concert as the rest of the audience without distortion. Sanchez-Dehesa, an engineer, recently showed that it's possible to build such an acoustic cloak, though he doubts we'll see one any time soon. "In principle, it is possible," he says, "but it might be impossible to make one." he adds. Other scientists are looking into ways to use larger metamaterials as shields around islands or oil rigs as protection from tsunamis. A tsunami is a giant destructive wave. The metamaterial would redirect the tsunami around the rig or island, and the wave would resume its energy on the other side without causing any harm.

单选题Ms. Breen has been living in town for only one year, yet she seems to be familiar with everyone who comes to the store.

单选题Fitness Movement The fitness movement that began in the late 1960s and early 1970s centered around aerobic exercise. Millions of individuals became engaged in a variety of aerobic activities, and 1 thousands of health spas developed around the country to capitalize on his 2 interest in fitness, particularly aerobic dancing for females. A number of fitness spas existed 3 to this aerobic fitness movement, even a national chain with spas in most major cities. However, their 4 was not on aerobics, but rather on weight-training programs designed to develop muscular mass, 5 , and endurance in their primarily male 6 . These fitness spas did not seem to benefit 7 from the aerobic fitness movement to better health, since medical opinion suggested that weight-training programs 8 few, if any, health benefits. In recent years, however, weight training has again become increasingly 9 for males and for females. Many 10 programs focus not only on developing muscular strength and endurance but on aerobic fitness as well. 11 , most physical fitness tests have usually included measures of muscular strength and endurance, not for health related reasons, but primarily 12 such fitness components have been related to performance in athletics. 13 , in recent years, evidence has shown that training programs designed primarily to improve muscular strength and endurance might also offer some health 14 as well. The American College of Sports Medicine now 15 that weight training be part of a total fitness program for healthy Americans.

单选题The man was sent to prison for driving {{U}}recklessly{{/U}}.

单选题Jack was dismissed. A. fired. B. fined C. exhausted D. criticized

单选题From my standpoint , you know, this thing is just ridiculous.

单选题Please be careful when you are drinking coffee in case you smudge the new carpet.A. crashB. polluteC. contaminateD. stain

单选题Nobody likes taking exams; exams (51) our own language can be stressful enough but somehow exams in a foreign language always seem to (52) more worry and anxiety. Well, the good news is that, if you (53) some simple steps, taking English language exams can be really quite (54) It won't exactly be fun, but it certainly shouldn't give you too many headaches or (55) nights. If you are planning to (56) one of the well - known exams such as Cambridge First Certificate, you will probably find that there's a preparation course (57) at a school near you. Cheek that the school has a good (58) of exam success and that the teacher is (59) . It is a good idea to ask if you will be given homework and (60) your written work will be marked by a teacher (61) knows the level of English (62) by the exam. If you take (63) exam preparation course, your teacher will give you all the information you need and you will find that (64) in a class helps you to study more effectively. But you will still need to (65) a lot of work yourself after all, the teacher can't take the exam for you !

单选题 The Spanish Flu Epidemic If you're worried about the possibility of a coming bird flu epidemic, you can take comfort in the fact that humanity has survived a similar influenza epidemic in the past. Starting its rounds at the end of World War I, the 1918 flu killed an estimated 50 million people. Popularly known as the Spanish Flu, this type of influenza was far worse than your common cold. Normally, influenza only kills those who are more vulnerable to disease, such as newborns, the old or the sick. However, the Spanish Flu was prone to killing the young and healthy. Often it would disable its victims in hours; within a day, they would be dead, typically from extreme cases of pneumonia (肺炎). The Spanish Flu was quite nasty-fast-spreading and deadly. It managed to spread across the globe, devastating the world. Then suddenly, after two years ravaging (蹂躏) the Earth, it disappeared as quickly as it had arisen. Despite its nickname, the Spanish Flu did not originate in Spain. Its true origins are unknown. Some believe it started in US forts and then spread to Europe as America joined the war; others think that it populated the trenches of the English and the French and eventually broke out in 1918. Regardless of where it started, eventually a fifth of the world population suffered the disease, with a global mortality rate (死亡率) estimated at 2.5% of the population. Modernity was partly to blame for the quick spread of the disease. It passed throughout the world on trade routes and shipping lines. It hit Northern America, Europe, Asia, Africa and the South Pacific. The war did not help at all-the movement of supplies and troops aided the spread of the Spanish Flu, as well as the trench warfare. Imagine the speed at which a virus can spread in a crowded ditch. The fast emergence of the virus in the trenches caused some soldiers to believe that the Spanish Flu was a new form of biological warfare. Luckily, the Spanish Flu simply vanished by 1920. It is believed the flu simply ran out of fuel to spread.

单选题Eleanor Roosevelt urged legislation to assist the poor and oppressed.