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Farming is still the world’s greatest industry. On average, over half of the population spend their lives ploughing the soil, planting seeds, harvesting crops, and raising animals which provide us with meat, milk, eggs, wool, leather, and many other products. Traditional farming, in which most of the hard work on the farm is done by manual labor and animals, is still practiced in many countries. But traditional methods cannot produce enough food to cope with the great explosion in population.Only with modern methods of farming—using machines to replace men and animals, artificial fertilizers to enrich the soil, and chemicals to keep weeds and diseases under control, can man hope to avoid a catastrophic world food shortage. Forming methods are well advanced in most parts of Europe and North America, and farmers elsewhere are being helped by such organizations as the United Nations Food and Agricultural Organization (FAO) to modernize as quickly as possible.Machinery has brought about the greatest revolution in farming. By far the most important machine is the tractor, which is used for pulling many kinds of implements—ploughs to break up the soil, drills to sow the seeds, trailers to carry manure, and so on. In this respect, it does the same kind of work as teams of horses, or oxen once did. But a tractor does more than just pull. It also provides power to drive other machinery, such as mowing machines, and potato harvesters.The standard type of tractor has two massive wheels at the rear and two small ones at the front, but those designed for traveling over heavy ground or for pulling heavy loads have caterpillar or crawler tracks. Tractors supply power to drive other machinery either through a pulley wheel driven by the engine or by means of what is called power take-off (p.t.o). In p.t.o drive, the moving part of the machine the tractor is pulling, such as the knife blade of a mower, is turned directly by a shaft driven by the engine.Among the many other farm machines, combine harvesters are probably the most important. They are so called because they combine the actions of reaping and threshing. Cereals are the main, but not the only crops that are harvested with the combine. Peas and beans can also be harvested with it.Growing plants take their nourishment from the soil. They need certain essential elements, particularly calcium, nitrogen, phosphorus, and potassium, if they are to grow well. It stands to reason that after every crop there will be less of these elements remaining in the soil for a subsequent crop. To ensure a good crop every time, farmers apply fertilizers to the soil before planting to replace the essential elements the previous crop removed.The farmer’s traditional fertilizer is farm-yard manure, a rotted mixture of dung and straw. It improves the texture of the soil as well. But there is not enough manure to supply the needs of a modern farmer, and artificial fertilizers are widely used instead. There are a variety of artificial fertilizers, each supplying certain of the essential elements. Sulphate of ammonia supplies nitrogen, super phosphate of lime supplies phosphorus, bone meal supplies both nitrogen and phosphorus, sulphate of potash supplies potassium, and there are many, many more. Super phosphate is probably one of the most widely used of all the fertilizers. Lime is also added to the soil on a large scale. It is valuable not only as a fertilizer but also as a soil conditioner.Of course, stimulating crops into better growth makes the weeds grow better, too! Fortunately the chemist has come to the aid of farmers and developed selective weed-killers, properly called herbicides, for use with their crops. Herbicides have a selective action in that they kill the weeds but leave the crop unharmed. They are used particularly with the cereal crops. Chemists have also developed a wide range of fungicides to kill fungus diseases, such as potato blight or rust n wheat, which could devastate the crops. Farmers wage continual war against insects, too. Maggots, beetles, and weevils can do untold damage if they are not checked. Again, modern science has produced powerful insecticides to protect crops against insect attack.1. What is the symbol of traditional farming?2. According to the author, tractor .3. To supply the needs of modern farming .4. It can be inferred from the passage that .5. The word “revolution” in line 1 of paragraph 3 can be best replaced by .6. The word “they” in line 2 of paragraph 5 refers to .7. The phrase “come to the aid of” in line 2 of the last paragraph most probably means .

People can be addicted to different things—for example, alcohol, drugs, certain foods, or even television. People who have such an addiction are compulsive; that is, they have a very powerful psychological need that they feel they must satisfy. According to psychologists, many people are compulsive spenders. They feel that they must spend money. This compulsion, like most others is irrational—impossible to explain reasonably. For compulsive spenders who buy on credit, charge accounts are even more exciting than money. In other words, compulsive spenders feel that with credit, they can do anything. Their pleasure in spending enormous amounts is actually greater than the pleasure that they get from the things they buy.There is even a special psychology of bargain hunting. To save money, of course, most people look for sales, low prices and discounts. Compulsive bargain hunters, however, often buy things that they don’t need just because they are cheap. They want to believe that they are helping their budgets, but they are really playing an exciting game. When they can buy something for less than other people, they feel that they are winning. Most people, experts claim, have two reasons for their behavior: a good reason for the things that they do and the real reason.It is not only scientists, of course, who understand the psychology of spending habits, but also business-people, Stores, companies, and advertisers use psychology to increase business. They consider people’s needs for love, power, or influence, their basic values, their beliefs and opinions and so on in their advertising and sales methods.Psychologists often use a method called ‘behavior therapy’ to help individuals solve their personality problems. In the same way, they can help people who feel that they have problems with money.Although behavior has many causes, most scientists seek to isolate single causes. This makes the scientific study of behavior hard. Many researchers in psychology use controlled experiments in which they can examine the effect of one factor at a time in a particular kind of behavior. Some investigators design experiments to test the behavioral effects of several factors in various combinations. Still other researchers study behavior in the ‘real’ world by observing people in their daily activities. Observing behavior outside controlled experiments cannot prove that one thing causes another. But studying people in the real world often helps scientists see the ways in which causes identified in experiments actually operate in people’s daily lives.Specialists in many fields study behavior. Psychologists and some biologists study animal behavior in controlled experiments. Other psychologists study individuals or small groups of people in controlled games or tasks to understand many aspects of behavior, including the reasons for people’s feelings, thoughts and motives. These studies help establish principles that can be used to explain, predict, and modify behavior. Educational researchers study how people behave in the classroom. In sociology, behavioral research focuses mainly on the behavior of people in large groups and social institutions, such as businesses, churches, governments, and hospitals. An anthropologist may live in an isolated community to study behavior patterns of a whole group.1. According to the psychologists, a compulsive spender is one who spends money .2. According to the writer, compulsive bargain hunters are in constant search of the lowest possible prices .3. The article is mainly about .4. From the passage we may safely conclude that compulsive spender or compulsive bargain hunters .5. From the passage, we know that scientific study of behavior is .6. A controlled experiment in this passage is one in which .7. We can infer that __.

Human beings are capable （1） thought; they are swayed by emotions. We can leave to the philosopher and the physician such questions （2） the power of the mind to abstract, to comprehend and to reason, the nature of instincts, the action and interaction of intellect and will and emotions. （3） when men think and feel deeply, their normal reaction is to wish to communicate their thoughts and their feelings. The sharing fulfills a （4） need in human nature. Men live in society; they do not normally live in isolation. When one human being wished to convey his （5） to another, he has to make use of a medium, a bridge. That bridge is language.The science （6） object is the study of language is known as Linguistics. The student of Linguistics is concerned with every aspect of this conveying of ideas from one mind to another, with language as a means of inter-communication, whether it is spoken, pictured or written. The more specialized branch of this study which is concerned only with spoken language, more specifically with the sounds used in speech, （7） known as Phonetics.Now even in this scientific age, communication is still （8） oral. It is still true to say the great majority of information is conveyed by means of the spoken word. It is self-evident that before any language can be written it must be spoken. It is, （9）, quite possible, as we know from examples up to own times, to have literature without literacy. The pen and the printing press merely hive visual permanence to messages which would otherwise have to be transmitted by the tongue and received by the ear. Writing is, of course, a powerful defense against the ravages of time or distance, a more permanent and reliable storehouse （10） human memory.

Passage 1Several promising drug development strategies are emerging in the fight against tuberculosis (TB), which continues to claim nearly two million lives worldwide each year, largely in developing countries. As the TB bacterium evolves to resist anti-TB drugs, and patients find it difficult to stick to existing drug regimes the search is on for both new drugs and good diagnostics. Some promising drugs are in early clinical trials, which could reduce the time needed to treat TB—but the odds are stacked against them because fewer than ten per cent of antibiotics that enter early clinical trials ever gain approval. But researches are finding that fields involving the study of genes, proteins and metabolism offer the potential to unlock new information about the bacterium and its interactions with people in unprecedented detail.Passage 2As far as Web 2.0 is concerned, bigger is definitely better. Bigger text, that is. Large text is easy on the eye, and coupled with snappy copywriting makes information easy to absorb. The layout of Web 2.0 sites might be described as minimal. With a focus on legibility and ease of use, good use is made of white space. White space allows important information to stand apart, provides rest for the eye, and imparts a sense of calm and order. Generous leading also makes text copy easier for the eye to follow. Some Web 2.0 layouts are so minimal that they verge on boring, but designed well, an uncluttered page can be incredibly tasteful. Friendly, informal copywriting allows a more personal relationship with website visitors.Passage 3The project management team must be careful not to confuse quality with grade. Low quality is always a problem; low grade may not be. Determining and delivering the required levels of both quality and grade are the responsibilities of the project manager and the project management team. In addition, quality improvement initiatives undertaken by the performing organization can improve the quality of the project management as well as the quality of the project product. However, there is an important difference that the project management team must be acutely aware of—the temporary nature of the project means that investments in product quality improvement, especially defect prevention and appraisal, must often be borne by the performing organization since the project may not last long enough to reap the rewards.

Passage 1肝脏是人体最大的腺体，它位于右上腹部。肝脏表面光滑，因血液供应丰富而呈暗红色。大约25%的心输出量流向肝脏。肝脏有许多重要的功能：1）营养物（蛋白质、碳水化合物和脂肪）、药物和毒素的摄取、储存和代谢。2）合成蛋白的产生和机体物质的代谢。Passage 2100多年前，世界上第一辆汽车的诞生让人们感受到速度带来的震撼。然而，汽车在给人类社会带来便捷的同时，消耗了大量的石油，而且每天排放大量污染物，对人类健康和生态环境造成严重危害。因此，研发节能与新能源汽车成为全球汽车业发展的主题。Passage 3管理是一种社会职能，隐藏在习俗、信念等传统里，以及政府政策和政治制度中，管理也是“文化”。人与人的关系正代替人与自然或人与物之间的关系成为相互交往的首要方式。人文文化从科学寻找自信心、理智能意念；科学从人文文化吸取朝向人的情感、价值观念。

TOPIC: In China, many companies, organizations, even universities, refuse to employ female school graduates. During economic recession, female employees are frequently the first to be laid off. Is it fair? Please write an essay to explain your position. Please use adequate material to support your position.

Diseases of the twenty-first century are inevitably be different from those of the twentieth century; just as our present illnesses have been quite different from those of the nineteenth century. Although our health is improving in many ways and we are living longer than in previous decades, new diseases and conditions threaten the quality of our lives. We have already observed some significant changes in the 1980s that foretold what health problems lie ahead in the twenty-first century:Diseases of the immune system, not just AIDS but various conditions of a deficient or overactive immune system, have reached epidemic proportions.The number of people suffering from viral conditions that are incurable with conventional therapies is increasing, and the number of newly defined viral conditions, such as the Epstein-Barr Virus and cytomegalovirus, is also increasing significantly.More and more bacterial infections are becoming resistant to commonly used antibiotics and are requiring stronger antibiotics, which also are net always successful in curing the infections.Allergies to foods, to common substances such as animal hairs and house dust, and to new chemicals are becoming more prevalent. One in seven Americans had an allergy in 1950, as many as one in five had an allergy in 1970, and approximately 75 million Americans, or nearly one in three, had an allergy in 1985.Chronic disability is affecting people more frequently at younger and younger ages. According to the National Center for Health Statistics, the percentage of children under 17 years of age who are limited in activity due to chronic conditions increased by 86% from 1967 to 1979.Mental disease is affecting more and more people. The National Institute of Mental Health estimated in 1984 that one in every five Americans had a mental disorder. This same study revealed that, during a six-month period, 8.3% of Americans suffered from an anxiety disorder, 6.4% had an alcohol or drug problem, and 6% had a mood disorder.In addition to these various trends, one of the more significant facts that will affect the future of health care is that larger percentage of the population will be over 65 years old. According to projections by the US Bureau of the Census, the size of the American population Over 65 in 1985 will have doubled by 2030.Futurists generally assume that twenty-first century medicine will include new and more-powerful drugs and various innovative technological interventions. However, futurists tend to ignore the serious problems presently arising from conventional medications. According to 1986 statistics, the average American receives 7.5 prescriptions a yeah This is a particularly frightening number because we all know there are people who have not been prescribed any medications in the past year, which means that someone else is getting their 7.5 drugs.Since most drugs have side effects, some of which are quite serious, and since the sick person is often prescribed several drugs at the same time, any of which may have even greater potential for side effects, it is no wonder that 50% of the time people do not even get their drug prescriptions filled. Additionally various studies have indicated that 25% to 90% of the time patients make errors in administering the medicines. Despite the respect that people generally show inward present-day physicians, there does not seem to be equal confidence in the treatments they prescribe.1. That diseases of the 21st century are different from those of 20th century is.2. Which of the following is true about diseases of the immune system?3. Which of the following statements is NOT true?4. We may infer from the passage that.5. According to the National Institute of Mental Health, in 1984, __.

April the 3rd was the day we attempted to reach Mount Everest. The morning saw us ail up and rushing about the bungalow at daybreak. We bumped down the nine miles of dusty track, each clutching a camera or one of the more delicate instruments to our chests in an endeavor to make our bodies absorb as many of the shocks from the bump track as possible. The ground staff was already busy on our arrival. The sheds where the aircraft were kept had been opened and the great machines were being manhandled out onto the tarmac. The bottles of oxygen were carefully placed in their clips and connected to the system. The vertical cameras were titled and tested, and air frames and engines were inspected and tested in every detail.Pilots and observers fussed around their equipment, trying on many times before readjusting straps, electric leads and oxygen feed pipes that had already been adjusted to a nicety. They then rechecked the charts which had been carefully prepared to allow accurately for the increasing wind speeds during the climb—all trying to keep themselves occupied during that tense half-hour wait for the return of the reconnaissance machine.There had been so much preparation for this flight, and there was still so much of the unknown about it, that the crews could not help being slightly affected by the general excitement. Waiting is always unpleasant, and we were all relieved to see the reconnaissance machine diving down through the dust haze. The Air Commodore who commanded it brought welcome news. Though he had been unable to climb above the dust, he had been able to see towards the mountains through the top of the haze and there was a cloudless sky. This was splendid: no cloud to mar the photography.We had promised not to attempt the flight if the wind exceeded 40 miles an hour, but this was the first time we had found the wind under 100 miles an hour. We worked out the implications and reckoned that, provided we did not spend more than fifteen minutes at the summit, we could get back inside our petrol endurance. We might wait for days and weeks and not get another opportunity. The Air Commodore weighed the position carefully and gave the word “Go”.1. The author and his colleagues held their instruments close to their chests because .2. When the members of the expedition arrived at the aerodrome, the ground staff were .3. The crews of the aircraft kept checking their equipment .4. The purpose of this expedition to Mount Everest was to .5. The pilots took the opportunity to .6. The word “tarmac” in line 6 of paragraph 1 most probably means .7. The word “They” in line 3 of paragraph 2 refers to __.

For untold centuries man depended almost entirely on his hunting ability to obtain food. From sunrise to sundown, armed with clubs and spears, and aided by trained wild dogs, he searched for game—his foremost source of food with his primitive weapons, the largest and swiftest animals often eluded him, and the hunter and his family frequently went for days without meat.While the men were hunting game, the women and children searched for edible vegetation. From nearby plants and trees they gathered berries, nuts, grain, and roots. These meager staples stayed the pain of hunger when the hunters returned empty handed. When the supplies of game and plants in an area were exhausted, the entire tribe was forced to move on to a new and hopefully better region. Thus man led a nomadic existence. He could never settle in one place for long because his growing population outstripped the available supply of food in the area.Then man made one of his greatest discoveries—agriculture. This revelation of raising plants and domesticating animals was one of the major steps in civilization. Agriculture did not by itself create civilization, but without it man could not have settled in one place long enough to build a permanent home. Anthropologists are uncertain about when or how man first learned to farm. They suggest it may have resulted from casual observation. A tribe or many tribes over a wide area might have stayed in one place long enough to see a true bear fruit for more than one season. They may also have observed that young plants grew out of ground to produce food as they matured.Or, as one anthropologist suggests, a handful of wild groin may have thrown onto the ground, and later the seeds grew into new plants. Regardless of the exact circumstances, man did eventually recognize that he could have a dependable source of food if he planted seeds and later harvested his crop.After man learned that he could grow food, the next step was mastering crop cultivation. The early farmer realized that he could grow more food if the seeds were covered with broken ground. This insight led to the making of the first farm equipment-sticks shaped into spades and hoes. From examination of the remains of the earliest known farming tools, archaeologists have determined that this occurred about seven thousand years ago. These implements were found in the area known as the Fertile Crescent, which lies between the east coast of the Mediterranean Sea and Persian Gulf. Evidence also indicates that the farmers of this area—possibly the first in the world—cultivated large wheat crops. To tend these crops, the hoe and spades were transformed into plows.About the same time as the growing of the first crops, man, relying on the experience he had gained in training wild dogs to aid in hunting, began domesticating other animals. Over the years, he developed herds of animals for food and to aid in his work.With the cultivation of crops and the domestication, of animals, man had a fairly dependable and permanent food supply. This accomplishment allowed him time for other work. Instead of spending most of his waking hours hunting for food, he was able to establish villages, and he had leisure time to ponder new ideas and keep records of events in his life. With the discovery of agriculture, man ceased his animal-like existence and began to build the foundation for civilization.1. The word “elude” in the first paragraph most probably means .2. What is the significance of raising plants and domesticating animals?3. From this passage we can conclude that .4. According to the passage, with the discovery of agriculture .5. During the period in which man was hunting for animals for food, man could never live in one place permanently because .6. With regard to when and how man first learned to farm, the passage .7. Man stopped his animal-like living after he .

The helicopter is an incredibly versatile machine. It can fly, straight up or down, hover like a fly, and go forwards, backwards, or sideways. It therefore needs no long, prepared runway like a normal airplane does. It can operate from a flat roof in the city or from a clearing in the jungle with equal ease. However, helicopters are nowhere near as fast as normal fixed-wing airplanes and have a top speed of only about 200 miles an hour.The helicopter has often been called the ‘flying windmill’ because of the long, rotating blades, or rotor, on top of its body. This main rotor serves as both propeller and wings to provide the thrust to drive the helicopter along and the lift to raise it off the ground. The rotor blades have the same aero-foil shapes as airplane wings and propellers to generate the required lift and thrust.When the main rotor rotates, the body of the helicopter lends to spin by reaction in the opposite direction. To counteract this effect, a small rotor is mounted sideways on the tail. The thrust produced by this tail rotor in normal flight just balances the turning tendency of the helicopter body which therefore remains steady. Both the main and the tail rotors are driven by the helicopter engine through the same gearbox. Another way of maintaining stability in the air is to have twin main rotors which each rotate in opposite directions. Then, the “spinning” tendency of one cancels that of the other.Movement of the helicopter in a direction—forwards, backwards, sideways, up or down—is achieved simply by varying the pitch of the rotor blades. The pitch is the angle at which the blades slice through or ‘bite’ the air. To fly straight upwards all the blades are set at the same sharp pitch. In this position they achieve maximum lift. To descend, the pitch of the blades is reduced so that the lift is insufficient to support the helicopter’s weight.The pilot adjusts the pitch for up or down movement by moving the collective-pitch stick. This is also linked to the engine throttles so that more power is applied as the pitch increases. This is to overcome the greater air resistance with the sharper pitch. Conversely, the engine is throttled back when the pitch is reduced for descent because there is less air resistance.To fly forwards, the pitch of the rotor blades is varied as they rotate. For forward motion, the pitch is made least at the front and gradually increased as the blade moves backwards. This has the effect of sweeping the air backwards, and therefore pushing the helicopter forwards. The same goes for any horizontal movement—the pitch is made least in the desired direction of travel. The cyclic-pitch stick controls the pitch of the rotor for horizontal flight.1. From the first paragraph we can infer that .2. What’s the basic function of the main rotor of a helicopter?3. The movement of the helicopter in any direction is controlled by .4. To fly forwards, a helicopter has to .5. The word “descend” in line 4 of paragraph 4 can be best replaced by .6. The phrase “This position” in line 4 of paragraph 4 refers to __.7. What is the most appropriate title for this passage?

For centuries coal has been one of the most important fuels, and it still is, although it is less important now than it once was. Other fuels, notably petroleum and natural gas, are replacing it. But coal is still widely used for domestic heating and in power stations for generating electricity. Enormous quantities of coal are made into gas, and for use in metal-smelting furnaces, and elsewhere. And coal provides valuable raw materials for the chemical industry, too. But here again, petroleum and natural gas are supplanting coal.We mine coal from the ground, just as we mine minerals and ores. The deposits may lie on or just below the surface or deep underground. It is in coal-mining that the greatest advances in mining methods have taken place. Continuous mining machines hew the coal from the coal face, where once the miners slaved. Lengthy conveyor systems convey away the hew coal. Diesel and battery locomotives haul wagons along miles of underground tunnels.We tend to call coal a mineral, too. But there is a great difference between coal and, say, iron ore. Iron ore is inorganic in origin, being formed as a result of inorganic, or non-living processes inside the Earth’s crust. Coal, on the other hand, is organic in origin, being derived from plants which once lived on the surface. It consists mainly of carbon. The actual proportion of carbon varies from one type of coal to another.Most of the coal in the world is derived from plants that grew in the Carboniferous Period of the Earth’s history, which lasted from about 350 million to about 280 million years ago. During this period whole regions of the Earth were covered in swamps, in which lived gigantic ferns and trees. The plants died and fell into the swamps. Bacteria acted upon the dead vegetable matter and caused it to decay. As time went on, the decomposing vegetable matter became covered with mud and clay, and then more plants grew, died, decayed, and so on. In places layer upon layer of decayed plant remains built up, sandwiched between mud and clay sediments. In time the Earth’s crust folded this way and that; heat and pressure changed the sediments into rock and forced out most of the water from the decayed matter, which changed into coal. Thus were the coal measures formed.Not all the coal was subjected to the same degrees of heat and pressure. Therefore there are different kinds of coals. Peat is not really a true coal, but it represents the first decomposition stage in the coal-forming process. Lignite, or brown coal, represents a further state in the process. It contains a little less moisture, and somewhat more carbon than peat. Next there is bituminous or soft coal, the most plentiful of the coals. It has a high carbon content and contains little moisture. The final product of the coal-making process is anthracite, or hard coal, which is over nine-tenths carbon and contains scarcely any moisture at all.1. The word “supplanting” in line 6 of paragraph 1 most probably means .2. The second paragraph is mainly about .3. What’s the difference between coal and iron ore?4. From the passage, we know that .5. What is the main topic of this passage?6. Paragraph 4 deals with .7. According to the passage, there are __ types of coal.

Leave a piece of fresh fish lying around for a few days in the warmth of summer and try to forget about it. You can’t! Within a day or so it starts to decay and gives off the indescribable smell only rotten fish can give off. Pick pears from a tree and forget to eat them and soon your pears will be ‘sleepy’, or over-ripe and mushy, and useless for any purpose. These are just two common examples of food spoilage that may occur.Fortunately today there are a great many ways of preserving foods that enable us to enjoy all kinds of meats, fruits, and vegetables out of season and from other countries.Just how and why do foods spoil? Why does fish go rotten, butter turn rancid, milk sour, and pears “sleepy”? Basically there are two means by which food spoilage occurs. One is by the growth of micro-organisms on the outside, and the other is by chemical changes on the inside. Micro-organisms such as yeasts, molds, and bacteria are always present in the air around us. They settle on food and, if the conditions are right, begin to break it down. Some yeasts tend to make food ferment. They change sugar into alcohol, which then turns into acid making the food taste sour. Molds tend to grow on moist foods. You have probably seen the greenish-colored mold on bread and on cheese. It starts as tiny white spores and grows into a greenish mass, on the surface at first and then gradually right through. The food develops a musty taste.The sour and musty foods are not necessarily harmful. But some kinds of bacterial spoilage can be dangerous. Certain bacteria produce toxins which cause food poisoning. The worst thing about them is that they may be present even where there are no outward signs of decay. Botulism is the most deadly form of food poisoning of this kind. It is almost always fatal. But the toxins are destroyed by cooking, as are most toxins. Chemical spoilage may occur as a result of several processes. Contact with the air oxidizes foods such as butter which contain fats and oils, and makes them rancid. Substances called enzymes, which are present in all living things, are responsible for food spoilage, too. Their action, if limited, is beneficial. For example, they act on meat and make it more tender.All methods of food preservation aim to prevent the growth of any micro-organisms, and prevent or arrest the action of other agents causing decay. Canning, bottling and freezing are the most common methods of food preservation today. Drying and curing are methods that have been practiced for centuries in one form or another, and they are still very important. Two up-to-date methods use radiation and antibiotics (especially for poultry) to sterilize and preserve foodstuffs, but they are not used on anywhere near the same scale as the other methods. Pasteurization is another method of temporary preservation used for milk.1. The word “sleepy” in line 4 of paragraph 1 most probably means .2. From paragraph 3, we can infer that .3. According to the author, some sour and musty foods are .4. The best title for this passage would be .5. The word “they” in line 3 of paragraph 4 refers to .6. Enzymes are .7. All of the following are mentioned as ways of food preservation methods EXCEPT __.

In the 19th century it was common to hear people in Europe and America say that the resources of the sea were unlimited. For example, a （1） biologist writing in the mid-1800s commented that all of the great sea fisheries are （2）. Today there’s evidence that the resources of the sea are as seriously threatened as （3） of the land and the air and the concern of conservationists now includes herring and cod （4） the African elephant, the Indian tiger and the American eagle. （5）, the threat to fish is more alarming in some ways than the threat to birds and land animals because fish are a much-needed food resource. Many people throughout the world depend on fish as an important part of their diets and a （6） in the fish supply could have （7） effects （8） hunger and population. Fishermen in the N.Atlantic alone annually （9） 20 billion pounds of fish （10） food demands. But it is important to recognize that these practices cannot continue without depleting fish resources within the next few years.

According to a United States law passed in 1986, states participating in daylight saving time _____ advance their clocks one hour on the last Sunday in April.

Great and significant music can, however, be written on themes that are, in themselves, _____.

Penguins do not suffer from the cold in Antarctica because their feathers _____ a protective oil.

Many farms in the Southern United States _____ hay and tobacco and export them to other parts of the country.

A report submitted to the United States Congress in 1971 emphatically recommended a _____ national effort to adopt metric system.

If an object is suspended from any point on the vertical line passing through its center of gravity, the object will remain _____.

I’ve _____ my trust I shouldn’t have believed in him so much.

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