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Early hunters needed a way to measure time.A．YB．NC．NG

Early hunters needed a way to measure time.

A．Y

B．N

C．NG

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第1题

根据以下内容，回答下列各题。 Man’s first real invention, and one of the most important inve

ntions in history, was the wheel．All transportation and every machine in the world depend on it．The wheel is the simplest yet perhaps the most remarkable of all inventions, because there are no wheels in nature-no living thing was ever created with wheels．How, then, did man come to invent the wheel？ Perhaps some early hunters found that they could roll the carcass of a heavy animal through the forest on logs more easily than they could carry it．However, the logs themselves weighed a lot． It must have taken a great prehistoric thinker to imagine two thin slices of log connected, at their centers by a string stick．This would roll along just as the logs did, yet be much lighter and easier to handle．Thus the wheel and axle came into being and with them the first carts． The wheel is important because _______．

A.it was man’s first real invention

B.all transportation depends on it

C.every machine depends on it

D.both B and C

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第2题

Playing organized sports is such a common experience in the United States that many childr

en and teenagers take them for granted. This is especially true 【B1】______ children from families and communities that have the resources needed to organize and 【B2】______ sports programs and make sure that there is easy 【B3】______ to participation opportunities. Children in low-income families and poor communities are 【B4】______ likely to take organized youth sports for granted because they often 【B5】______ the resources needed to pay for participation 【B6】______ , equipment, and transportation to practices and games 【B7】______ their communities do not have resources to build and 【B8】______ sports fields and facilities.

Organized youth sports 【B9】______ appeared during the early 20th century in the United States and other wealthy nations. They were originally developed 【B10】______ some educators and developmental experts 【B11】______ that the behavior. and character of children were 【B12】______ influenced by their social surroundings and everyday experiences. This 【B13】______ many people to believe that if you could organize the experiences of children in 【B14】______ ways, you could influence the kinds of adults that those children would become.

This belief that the social 【B15】______ influenced a person's overall development was very 【B16】______ to people interested in progress and reform. in the United States 【B17】______ the beginning of the 20th century. It caused them to think about 【B18】______ they might control the experiences of children to 【B19】______ responsible and productive adults. They believed strongly that democracy depended on responsibility and that a 【B20】______ capitalist economy depended on the productivity of workers.

【B1】

A．among

B．within

C．on

D．towards

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第3题

One of medicine's fundamental beliefs about pregnancy and the development of the human fet

us has been challenged. Until recently, it was thought that the fetus was a parasite capable of extracting all the nutrients it needed from the mother. It is now realized that adequate nutrition during the entire course of the pregnancy is necessary for proper fetal development.

In early pregnancy, certain changes occur in the mother's gastrointestinal tract, resulting in more efficient absorption of specific nutrients, such as iron and calcium. Furthermore, the maternal blood supply increases, so that nutrients can be transported via the uterine and placental blood systems: If the mother is undernourished, this "lifeline" to the fetus will be inadequately developed. Finally, fat is accumulated within the body to store the energy necessary for lactation (milk production), This preparation for lactation is so important that if the mother is inadequately nourished, it will take place even at the expense of fetal growth. It is a logical developmental occurrence, since in the natural world, no infant can survive without successful breastfeeding, and thus fetal growth is less of a priority.

According to the passage, which of the following is required for lactation？

A．Fat storage.

B．Iron and calcium.

C．Increased blood supply.

D．A well-nourished placenta.

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第4题

听力原文： In the early 1800s, the paper industry was still using rags as its basic source

of fiber as it had for many centuries. However, the rag supply couldn’t keep up with the growing demand for paper. The United States alone was using 250 thou sand tons of rags each year. And a quarter of that had to be imported. It was clear that a new source of fiber was needed to keep up with the demand for paper. The answer to this problem turned out to be paper made from wood pulp, something that was abundantly available in North America. In Canada, the first wood pulp mill was set up in 1866, and it was immediately successful. But while wood pulp solved the problem of quantity, it created a problem of quality. Wood contains a substance called lignin. The simplest way to make large quantities of cheap paper involves leaving the lignin in the wood pulp. But lignin is acidic and its presence in paper has shorted the life expectancy of paper from several centuries for rag paper to less than a century for paper made from wood pulp. This means that books printed less than a hundred years ago are already turning yellow and beginning to disintegrate, even though books printed much earlier may be in fine condition. This is bad enough for the older books on your bookshelf, and it poses a huge problem for libraries and the collections of government documents, too.

The speaker mainly discusses ______.

A．the growth of the printing industry

B．the history of paper-making

C．the use of paper in the 19th century

D．the composition of wood fiber

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第5题

The mental health movement in the United States began with a period of considerable enligh

tenment. Dorothea Dix was shocked to find the mentally iii in jails and almshouses and crusaded for the establishment of asylums in which people could receive humane care in hospital-like environments and treatment, which might help restore them to sanity. By the mid-1800s, 20 states had established asylums, but during the late 1800s and early 1900s, in the face of economic depression, legislatures were unable to appropriate sufficient funds for decent care. Asylums became overcrowded and prisonlike. Additionally, patients were more resistant to treatment than the pioneers in the mental health field had anticipated, and security and restraint were needed to protect patients and others. Mental institutions became frightening and depressing places in which the rights of patients were all but forgotten.

These conditions continued until after Word War Ⅱ. At that time, new treatments were discovered for some major mental illnesses therefore considered untreatable (penicillin for syphilis of the brain and insulin treatment for schizophrenia and depressions), and a succession of books, motion pictures, and newspaper exposes called attention to the plight of the mentally ill. Improvements were made, and Dr. David Vail's. Humane practices program is a beacon for today. But changes were slow in coming until the early 1960s. At that time, the Civil Rights Movement led lawyers to investigate America's prisons, which were disproportionately populated by blacks, and they in turn followed prisoners into the only institutions that were worse than the prisons——the hospitals for the criminally insane. The prisons were rifled with angry young men who, encouraged by legal support, were quick to demand their fights. The hospitals for the criminally insane, by contrast, were populated with people who were considered "crazy" and who were often kept obediently in their place through the use of severe bodily restraints and large doses of major tranquilizers. The young cadre of public interest lawyers liked their role in the mental hospitals. The lawyers found a population that was both passive and easy to champion. These were, after all, people who, unlike criminals, had done nothing wrong. And in many states they were being kept in horrendous institutions, an injustice which, once exposed was bound to shock the public and, particularly, the judicial conscience.

Judicial interventions have had some definite positive effects, but there is growing awareness that courts cannot provide the standards and the review mechanisms that assure good patient care. The details of providing day-to-day care simple cannot be mandated by a court so it is time to take from the courts the responsibility for delivery of mental health care and assurance of patient fights and return it to the state mental health administrators to whom the mandate was originally given. Though it is a difficult task, administrators must undertake to write roles and standards and to provide the training and surveillance to assure that treatment is given and patients' rights are respected.

The main purpose of the passage is to ______.

A．discuss the influence of Dorothea Dix on the mental health movement

B．shock the reader with vivid descriptions of asylums

C．increase public awareness of the plight of the mentally ill

D．provide a historical perspective on problems of mental health care

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第6题

Robots May Allow Surgery in Space Small robots designed by University of Nebraska research

Robots May Allow Surgery in Space

Small robots designed by University of Nebraska researchers may allow doctors on Earth to help perform. surgery on patients in space.

The tiny, wheeled robots, （51）are about 3 inches tall and as wide as a lipstick case, can be slipped into small incisions(切口)and computer-controlled by surgeons in different locations. Some robots are equipped（52）cameras and lights and can send images back to surgeons and others have surgical tools attached that can be（53）remotely.

“We think this is going to （54）open surgery, ”Dr Dmitry Oleynikov said at a news conference. Oleynikov is a （55）in computer-assisted surgery at the University of Nebraska Medical Center in Omaha.

Officials hope that NASA will teach（56）to use the robots soon enough so that surgeries could one day be performed in space.

On earth, the surgeons could control the robots themselves（57）other locations. For example, the robots could enable surgeons in other places to （58）on injured soldiers on the front line. Researchers plan tp seek federal regulatory（59）early nest year. Tests on animals have been successful, and tests on humans in England will begin very soon.

The camera-carrying robots can provide（60）of affected areas and the ones with surgical tools will be able to maneuver(操控)inside the body in ways surgeons' hands can't. The views from the camera-carrying robots are （61）than the naked eye, because they（62）back color images that are magnified(放大). Because several robots can be inserted through one incision, they could reduce the amount and （63）of cuts needed for surgery, which would decrease recovery time. This is particularly（64）to those patients who have been debilitated(使虚弱)by long illness.

Eventually, Oleynikov said, the tiny robots may enable surgeons to work without ever（65）their hands in patients' bodies. “That's the goal, ”Oleynikov said. “It's getting easier and easier. We can do even more with these devices. ”

A．since

B．when

C．which

D．as

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第7题

Moderate drinking reduces stroke risk, study confirms. Similar to the way a drink or two a

day protects against heart attacks, moderate alcohol consumption wards off strokes, a new study found.

The study also found that the type of alcohol consumed -- beer, wine or liqour -- was unimportant. Any of them, or a combination, was protective, researchers reported in today's Journal of the American Medical Association. "No study has shown benefit in recommending alcohol consumption to those who do not drink", cautioned the authors, led by Dr. Ralph L. Sacco of Columbia University College of Physicians and Surgeons in New York. But the new data support the guidelines of the National Stroke Association, which say moderate drinkers may protect themselves from strokes by continuing to consume alcohol, the authors said.

The protective effect of moderate drinking against heart attacks is well established, but the data has been conflicting about alcohol and strokes, the authors said. The new study helps settle the question and is the first to find blacks and Hispanics benefit as well as whites, according to the authors. Further research is needed among other groups, such as Asian, whom past studies suggest may get no stroke protection from alcohol or may even be put at greater risk.

Among groups where the protective effect exists, its mechanism appears to differ from the protective effect against heart attacks, which occurs through boosts in levels of so-called "good" cholesterol, the authors said. They speculated alcohol may protect against stroke by acting on some other blood trait, such as the tendency of blood platelets to clump, which is key in forming the blood trait, such as the tendency of blood platelets to clump, which is key in forming the blood clots that can cause strikes.

The researchers studied 677 New York residents who lived in the northern part of Manhattan and had strokes between July 1,1993, and June, 1997. After taking into account differences in other factors that could affect stroke risk, such as high blood pressure, the researchers estimated that subjects who consumed up to two alcoholic drinks daily were only half as likely to have suffered clot-type strokes as nondrinkers. Clot-type strokes account for 80 percent of all strokes, a leading cause of US deaths and disability. Stroke risk increased with heavier drinking. At seven drinks per day, risk was almost triple that of moderate drinkers.

An expert spokesman for the American Heart Association, who was not involved in the study, said it was well-done and important information. But it shouldn't be interpreted to mean, "I can have two drinks and therefore not worry about my high blood pressure or worry about my cholesterol," said Dr. Edgar J. Kenton, an associate professor of clinical neurology at Thomas Jefferson University Medical College in Philadelphia. Instead, he said, the study provides good reason to do further research and to add alcohol to the list of modifiable risk factors for stroke.

The new study conducted by Dr. Sacco and his colleagues is unique in that ______.

A．it refutes early studies on the protective effect of moderate drinking against heart attack

B．it confirms early studies of moderate drinking against heart attacks

C．it helps to resolve the disputes over the effect of moderate drinking against stroke

D．it finds that moderate drinking can benefit people of different races equally well

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第8题

A situation analysis can help define the problem and make clear what additional information () .

A.is needed

B.needed

C.needs

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