单选题 A. So far, we have not known exactly yet whether mouth-to-mouth breathing is really useless in CPR. B. Only ten percent of the victims treated with traditional CPR survived with good brain ability. C. CPR keeps blood and oxygen flowing to the heart and brain. D. His studies show that many people do not want to perform mouth-to-mouth breathing on a stranger for fear of getting a disease. E. It said people should increase the number of chest presses from fifteen to thirty for every two breaths given. F. No mouth-to-mouth rescue breaths were given to them.

单选题Researchers have known for years that animals have a "clock" somewhere in their brains a control-centre that regulates circadian(生物节奏的) rhythms. Circadian rhythms are the body's daily biological cycles, controlling such activities as sleep and wakefulness. In November 1988, neuroscientists at the University of Virginia in Charlotteville reported that the supra chasmatic nucleus(SCN), a small cluster(束)of cells in the middle of the brain that neuroscientists have long suspected of playing a role in daily rhythms, is the long-sought biological clock. The investigators performed a series of tissue-transplant experiments with hamsters (仓鼠). Some of the animals were normal hamsters, which have a circadian cycle of 24 hours; the others were mutant(变异型)hamsters whose cycles were only 20 or 22 hours long. The scientists first removed the SCN from the brans of the hamsters in both groups. They then implanted an SCN from a mutant hamster into the brain of each normal animal, and vice versa. When the hamsters had recovered from their operations, the circadian rhythms of the two groups were reversed. The normal hamsters had a daily cycle of 20 to 22 hours, and the mutants were on a 24-hour cycle. The identification of the internal clock is an important stepping-stone in understanding the basic, automatic mechanisms of brain function. It may also help in finding ways to relieve human sleep disorders.

单选题Keep on Fighting Turning once again to the question of invasion, I would observe that there has never been a period in all these long centuries of which we boast when an absolute guarantee against invasion, still less against serious raids, could have been given to our people. In the days of Napoleon the same wind which would have carried his transports across the Channel might have driven away the blockading (封锁) fleet. There was always the chance, and it is that chance which has excited and befooled (愚弄的) the imaginations of many continental tyrants. Many are the tales that are told. We are assured that novel methods will be adopted, and when we see the originality of malice (怨恨), the ingenuity of aggression, which our enemy displays, we may certainly prepare ourselves for every kind of novel stratagem (战略) and every kind of brutal and treacherous (奸诈的) maneuver (花招). I think that no idea is so outlandish (古怪的) that it should not be considered and viewed with a searching, but at the same time, I hope, with a steady eye. We must never forget the solid assurances of sea power and those which belong to air power if it can be locally exercised. I have, myself, full confidence that if all do their duty, if nothing is neglected, and if the best arrangements are made, as they are being made, we shall prove ourselves once again able to defend our island home, to ride out the storm of war, and to outlive the menace (威胁) of tyranny, if necessary for years, if necessary alone. At any rate, that is what we are going to try to do. This is the resolve of his Majesty"s government—every man of them. This is the will of parliament and the nation. The British Empire and the French republic, linked together in their cause and in their need, will defend to the death their native soil, aiding each other like good comrades to the utmost of their strength. Even though large tracts of Europe and many old and famous states have fallen or may fall into the grip of the Gestapo and all the odious (可憎的) apparatus of Nazi rule, we shall not flag (变弱) or fail. We shall go on to the end, we shall fight in France, we shall fight on the seas and oceans, we shall fight with growing confidence and growing strength in the air, we shall defend our island, whatever the cost might be, we shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills, we shall never surrender, and even if, which I do not for a moment believe, this island or a large part of it were subjugated (征服) and starving, then our empire beyond the seas, armed and guarded by the British fleet, would carry on the struggle, until, in God"s good time, the new world, with its power and might, steps forth to the rescue and the liberation of the old.

单选题These are our motives for doing it.

单选题One Good Reason to Let Smallpox Live It's now a fair bet that we will never see the total extinction of the smallpox virus. The idea was to cap the glorious achievement of 1980, when smallpox was eradicated in the wild, by destroying the killer virus in the last two labs that are supposed to have it-one in the US and one in Russia. If smallpox had truly gone from the planet, what point was there in keeping these reserves? (51) reality, of course, it was naive to (52) that everyone would let (53) of such a potent potential weapon. 1 Undoubtedly several nations still have (54) vials. (55) the last "official" stocks of live virus bred mistrust of the US and Russia, (56) no obvious gain. Now American researchers have (57) an animal model of the human disease, opening the (58) for tests on new treatments and vaccines. So one again there's a good reason to (59) the virus-just in (60) the disease puts in a reappearance. How do we (61) with the mistrust of the US and Russia? (62) Keep the virus (63) international auspices in a well-guarded UN laboratory that's open to all countries. The US will object, of course, just as it rejects a multilateral approach to just about everything. But it doesn't (64) the idea is wrong. If the virus (65) useful, the let's make it the servant of all humanity—not just a part of it.

单选题The baby's chances of developing cancer were said to be

单选题The healthier diet has helped schoolchildren improve academically.

单选题They Uscattered/U after dinner.

单选题 Smoking Since 1989, numerous studies have been conducted to determine whether smoking is a health hazard. The trend of the evidence has been consistent and indicates that there is a serious health risk. Research teams have conducted studies that show beyond all reasonable doubt that tobacco smoking is associated with a shortened life expectancy. Cigarette smoking is believed by most research workers in this field to be an important factor in the development of cancer of the lungs and cancer of the throat and is believed to be related to cancer of some other organs of the body. Male cigarette smokers have a higher death rate from heart disease than non-smoking males. Female smokers are thought to be less affected because they do not breathe in the smoke so deeply. Apart from statistics, it might be helpful to look at what tobacco does to the human body. Smoke is a mixture of gases, vaporized chemicals, minute particles of ash and other solids. There is also nicotine, which is powerful poison, and black tar. As smoke is breathed in, all those components form deposits on the membranes of the lungs. One point of concentration is where the air tube and bronchus divides. Most lung cancer begins at this point. Filters and low tar tobacco are claimed to make smoking to some extent safer, but they can only slightly reduce, not eliminate the hazards.

单选题 下面有3篇短文，每篇短文后有5道题。请根据短文内容，为每题确定1个最佳选项。{{B}}第一篇{{/B}} {{B}}Sleepwalking (梦游){{/B}} Not all sleep is the same every night. We experience some deep, quiet sleep and some active sleep, which is when dreams happen. You might think sleepwalking would happen during active sleep, but a person isn't physically active during active sleep. Sleepwalking usually happens in the first few hours of sleep in the stage called slow-wave or deep sleep. Not all sleepwalkers actually walk. Some simply sit up or stand in bed or act like they're awake when in fact, they're asleep! Most, however, do get up and move around for a few seconds or for as long as half an hour. Sleepwalkers' eyes are open, but they don't see the same way they do when they're awake and often think they're in different rooms of the house or different places altogether. Sleepwalkers tend to go back to bed on their own and they won't remember it in the morning. Researchers estimate that about 15% of kids sleepwalk regularly. Sleepwalking may run in families (在家族中世代相传) and sometimes occurs when a person is sick, has a fever, is not getting enough sleep, or is stressed (紧张的). If sleepwalking occurs frequently, every night or so, it's a good idea for your mom or dad to take you to see your doctor. But occasional sleepwalking generally isn't something to worry about, although it may look funny or even scary (骇人的) for the people who see a sleepwalker in action. Although occasional sleepwalking isn't a big deal, it's important, of course, that the person is kept safe. Precautions (预防措施) should be taken so the person is less likely to fall down, run into something, or walk out the front door while sleepwalking.

单选题 阅读下面的短文，文中有15处空白，每处空白给出了4个选项，请根据短文的内容从4个选项中选择1个最佳答案。 {{B}} Scientists Develop Ways of Detecting Heart Attack{{/B}} German researchers have{{U}} (1) {{/U}}a new generation of defibrillators and early warning software aimed at offering heart patients greater protection{{U}} (2) {{/U}}sudden death from cardiac arrest. In Germany alone around 100,000 people die annually as a result of cardiac arrest and many of these cases{{U}} (3) {{/U}}by disruption to the heart's rhythm. Those most at risk are Patients who have{{U}} (4) {{/U}}suffered a heart attack and for years the use of defibrillators has proved useful in diagnosing{{U}} (5) {{/U}}disruptions to heart rhythms and correcting them automatically by intervening within seconds. These devices{{U}} (6) {{/U}}a range of functions such as that of pacemaker. Heart specialists at Freiburg's University Clinic have now achieved a breakthrough with all implanted defibrillator{{U}} (7) {{/U}}of generating a six-channel electrocardiogram(ECG) within the body. This integrated system allows early diagnosis of{{U}} (8) {{/U}}blood-flow problems and a pending heart attack. It will be implanted in patients for the first time this year. Meanwhile, researchers at the Fraunhofer Institute for Applied Mathematics in Kaiserslautern have developed new computer software that renders the evaluation of ECG data{{U}} (9) {{/U}}. The overwhelming{{U}} (10) {{/U}}of patients at risk will not have an implanted defibrillator and must for this reason undergo regular ECGs. "Many of the current programs only{{U}} (11) {{/U}}into account a linear correlation of the data. We are, however, making use{{U}} (12) {{/U}}a non-linear process that reveals the chaotic patterns of heart beats as an open and complex system." Hagen Knaf says."{{U}} (13) {{/U}}changes in the heart beats over time can be monitored and individual variations in patients taken into account." An old study of ECG data, based{{U}} (14) {{/U}}600 Patients who had suffered a subsequent heart attack, enabled the researchers to compare risks and to show{{U}} (15) {{/U}}the new software evaluates the data considerably better.

单选题Ten years after the event, her death still remains a Upuzzle/U.

单选题It is very difficult for a child to adhere to rules.______

单选题Accurate prediction of earthquakes still needs to take more years.A. definiteB. preparedC. timelyD. precise

单选题The mountains look glorious at sunrise.

单选题 下面有3篇短文，每篇短文后有5道题，每题后面有4个选项。请仔细阅读短文并根据短文回答其后面的问题。 {{B}}第一篇{{/B}} {{B}} Shakespeare{{/B}} When talking about the world's greatest poet and greatest dramatist, only one name can possible suggest itself; that of William Shakespeare. Nearly every Englishman has some knowledge, however slight, of the work of this greatest writer. We use words, phrases and quotations form Shakespeare's writings that have become part of the common property of English-speaking people. Most of the time we are probably unaware of the source of the words we use. For example, and old lady, after seeing a performance of Hamlet complained, "It was full of well-known proverbs and quotations!" Shakespeare made full use of the great resources of the English language. Most of us use about five thousand words in our normal employment of English; Shakespeare in his works used about twenty-five thousand! There is probably no better way for a foreigner (or an Englishman) to appreciate the richness and variety of the English language than by studying the various ways in which Shakespeare used it. Such a study is well worth the effort, even thought some aspects of English and the meaning of many words, have changed since Shakespeare's day. It is a pity that we know so little about the life of the greatest English author. We only know that he was born in 1564 in Stratford on-Avon, and that then died there in 1616. He almost certainly attended the Grammar School in the town, but of this we cannot be sure. We know he was married there in 1582 and had three children. We know that he spent much of his life in London, writing his masterpieces. But this is almost all that we do know. However, what is important about Shakespeare's life is not its incidental details but its products, the plays and the poems. For many years scholars have been trying to add a few facts about Shakespeare's life to the small number we already posses and for an equally long time critics have been theorizing about the plays. Sometimes indeed, it seems that the poetry of Shakespeare will disappear beneath the great mass of comment that has been written upon it. Fortunately this is not likely to happen. Shakespeare's poetry and Shakespeare's characters (Macbeth, Othello, Hamlet and all the others) have long delighted not just the English but lovers of literature everywhere, and will continue to do so after the scholars and commentators and all their works have been forgotten.

单选题The news will horrify everyone.

单选题Companion of My Life Most people have had a dog or wanted one as their companion at some time in their lives. If you are thinking of buying a dog, however, you should first decide what sort of companion you need and whether the dog is likely to be happy in the surroundings you can provide. Specialists" advice is useful to help you choose the most suitable kind of dog. But in part the decision depends on common sense. Different dogs were originally developed to perform specific tasks. So, if you want a dog to protect you or your house, for example, you should choose the one that has the right size and characteristics. You must also be ready to devote a great deal of time to training the dog when it is young and give it the exercise it needs throughout its life, unless you live in the countryside and can let it run freely. Dogs are demanding pets. Cats love the house and so are satisfactory with their place where there is secure, but a dog is loyal to its master and consequently wants him to show proof of his affection. The best time to buy a baby dog is when it is between 6 and 8 weeks old so that it can transfer its love for its mother to its master. If baby dogs have not established a relationship with the human being until they are over three months old, their strong relationship will always be with dogs. They are likely to be too shy when they are brought out into the world to become good pets.

单选题Obesity: the Scourge of the Western World Obesity is rapidly becoming a new scourge of the western world, delegates agreed at the 11th European Conference on the issue in Vienna Wednesday to Saturday. According to statements before the opening of the conference — of 2,000 specialists from more than 50 countries — 1.2 billion people worldwide are overweight, and 250 million are obese. Professor Bernhard Ludvik of Vienna General Hospital said, "Obesity is a chronic illness. In Germany, 20 percent of the people are already affected, but in Japan only one percent. " But he said that there was hope for sufferers thanks to the new scientific discoveries and medication. Professor Friedrich Hopichler of Salzberg said, "We are living in the new age (but) with the metabolism of a stone-age man." "I have just been to the United States. It is really terrible. A pizza shop is springing up on every comer. We have been overrun by fast food and Coca-Cola-ization. " Many of the experts stressed that obesity was a potential killer. Hopichler said, "Eighty percent of all diabetics are obese, also fifty percent of all patients with high blood pressure and fifty percent with adipose tissue complaints. " "Ten percent more weight means thirteen percent more risk of heart disease. Reducing one's weight by ten percent leads to thirteen percent lower blood pressure. " Another expert Hermann Toplak said that the state health services should improve their financing of preventive programs. "Though the health insurance pays for surgery (such as reducing the size of the stomach) when the body-mass index is more than 40. That is equivalent to a weight of 116 kilograms for a height of 1.70 meters. One should start earlier. " Ludvik said that prevention should begin in school. "Child obesity (fat deposits) correlates with the time which children spend in front of TV sets. " The consequences were only apparent later on. No more than fifteen per cent of obese people lived to the average life expectancy for their population group.

单选题We packed up the things we had accumulated (积累) over the {{U}}last{{/U}} three years and left. A. late B. recent C. past D. final