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Trees should only be pruned when there is a good and clear reason for doing so and, fortunately,the number of such reasons is small. Pruning involves the cutting away of overgrown and unwanted branches, and the inexperienced gardener can be encouraged by the thought that more damage results from doing it unnecessarily than from leaving the tree to grow in its own way.First, pruning may be done to make sure that trees have a desired shape or size. The object may be to get a tree of the right height, and at the same time to help the growth of small side branches which will thicken its appearance or give it a special shape. Secondly, pruning may be done to make the tree healthier. You may cut diseased or dead wood, or branches that are rubbing against each other and thus cause wounds. The health of a tree may be encouraged by removing branches that are blocking up the centre and so preventing the free movement of air.One result of pruning is that an open wound is left on the tree and this provides an easy entry for disease, but it is a wound that will heal. Often there is a race between the healing and the disease as to whether the tree will live or die, so that there is a period when the tree is at risk. It should be the aim of every gardener to reduce that risk of death as far as possible. It is essential to make the area,which has been pruned, smooth and clean, for healing will be slowed down by roughness. You should allow the cut surface to dry for a few hours and then paint it with one of the substances available from garden shops produced especially for this purpose. Pruning is usually without interference from the leaves and also it is very unlikely that the cuts you make will bleed. If this does happen, it is, of course, impossible to paint them properly.1.Pruning should be done to( ).2.Trees become unhealthy if the gardener( ).3.Why is a special substance painted on the tree?4.A good gardener prunes a tree( ).5.What was the author’s purpose when writing this passage?

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Of the thousands of different kinds of animals that exist in the world man has learned to make friends with an enormous number. Some are pets, which offer him companion- ship; some give protection, and some do hard work which man cannot do for himself. Dogs, which serve man in all three capacities, are found in various breeds in all countries of the world. The Husky can live in the cold polar regions, and the Saluki is at home in the hottest parts of Central Africa. The inhabitants of certain countries are dependent for their very lives on the camel. In the West Indies the little donkey, strong and sure-footed ,carrying heavy loads even in mountainous places,is a familiar sight.Trained and tamed for many generations, domestic animals are not accustomed to roa- ming in search of food and shelter. They look to their masters to provide for their needs, and as long as these are supplied, they are content to do what their masters require.All domestic animals need proper food. It must be suitable for them, sufficient in quantity,fresh and clean. Some people feed a pet dog or cat on odds and ends of table scraps, and then wonder why the animal seems listless and dull. The quantity of food de- pends on the size of the animal and the amount of exercise it takes. Overfeeding is as bad as underfeeding. Containers for food and water must be washed regularly if the animal is to maintain good health.Even well cared animals may sometimes fall ill. If this happens, the wise master seeks the best advice he can get. All sorts of medicines and treatments are available for sick ani- mals, and in some countries organizations exist to provide them free or at a cheap price. Useful, friendly,hardworking animals deserve to have some time,money and at- tention spent on their health.1.What main idea does the author want to convey in the first paragraph?2.When an animal is underfed, it will probably( ).3.Which of the following is NOT true of dogs according to the passage?4.To keep a domestic animal physically fit, its owner is advised( ).5.Which of the following would be best TITLE for this passage?  

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Which is safer—staying home, traveling to work on public transport, or working in the office? Surprisingly, each of these carries the same risk, which is very low. However, what about flying compared to working in the chemical industry? Unfortunately,the for- mer is 65 times riskier than the latter! In fact, the accident rate of workers in the chemical industry is less than that of almost any of human activity, and almost as safe as staying at home.The trouble with the chemical industry is that when things go wrong they often cause death to those living nearby. It is this which makes chemical accidents so newsworthy. For- tunately, they are extremely rare. The most famous ones happened at Texas City (1947), Flixborough (1974),Seveso (1976),Pemex (1984) and Bhopal (1984). Some of these are always in the minds of the people even though the loss of life was small. No one died at Seveso, and only 28 workers at Flixborough. The worst accident of all was Bhopal, where up to 3,000 were killed. The Texas City explosion of fertilizer killed 552. The Pemex fire at a storage plant for natural gas in the suburbs of Mexico City took 542 lives,just a month before the unfortunate event at Bhopal.Some experts have discussed these accidents and used each accident to illustrate a par- ticular danger. Thus the Texas City explosion was caused by tons of ammonium nitrate (硝酸铵),which is safe unless stored in great quantity. The Flixborough fireball was the fault of management, which took risks to keep production going during essential re- pairs. The Seveso accident shows what happens if the local authorities lack knowledge of the danger on their doorstep. When the poisonous gas drifted over the town, local leaders were incapable of taking effective action. The Pemex fire was made worse by an overloaded site in an overcrowded suburb. The fire set off a chain reaction of exploding storage tanks. Yet, by a miracle, the two largest tanks did not explode. Had they caught fire, then 3,000 strong rescue team and fire fighters would all have died.1.Which of the following statements is true?2.Chemical accidents are usually important enough to be reported as news because3.According to the passage,the chemical accident that caused by the fault of manage- ment happened at( )4.From the passage we know that ammonium nitrate is a kind of( ).5.From the discussion among some experts,we may conclude that( ).

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The dimensions of tourism are astonishing. In 2012,the U. N. tourism organization celebrated reaching 1 billion international trips in a single year. In gross economic power it is in the same company as oil, energy, finance and agriculture. At least one out of every ten people around the world is employed by the industry, according to Wolfgang Weinz of the International Labour Organization.Travel has also become a default fund-raising technique. (1) Today poor nations see tourism as their best bet out of poverty,second only to oil and energy as the major engine of development. Thailand is the world’s biggest exporter of rice, yet its tourism is its num- ber-one money earner. Costa Rica has turned its wilderness into a venue for highly profita- ble ecotcurism. As soon as Sri Lanka, and now Burma,began seeing an end to conflict, they opened the door to a rush of tourists. After the Arab Spring uprising, Egypt sent out a plea to cruise companies and tour operators to return and kick-start the economy (2)The U. N. tourism organization now places poverty reduction as one of its top ob- jectives,along with the high-minded ideals of improving international peace and prosperi-ty. Since the end of the Cold War and the opening of the world for travel,tourism has be- come an important source of foreign exchange for the world’s poorest nations, often the only one. While tourism requires some infrastructure, from airfields to modern high- ways. It is less expensive than building factories. In theory, poor countries should be able to use the new revenue from the tourism industry to pay for the infrastructure while raising standards of living and improving the environment. One hundred of the world’s poorest na- tions do earn up to 5 percent of their gross national product from foreign tourists who mar- vel at their exotic customs,buy suitcases of souvenirs and take innumerable photographs of stunning landscapes.(3)But just as tourism is capable of lifting a nation out of poverty,it is just as likely to pollute the environment,reduce standards of living for the poor because the profits go to international hotel chains and corrupt local elites,and cater to the worst of tourism, in- cluding condemning children the exploitation of sex tourism. Like any major industry, tourism has a serious downside, especially since tourism and travel is underestimated as a global powerhouse,its study and regulation is spotty at best.(4)Tourism is one of those double-edged swords that may look like an easy way to earn desperately needed money but can ravage wilderness areas and undermine native cultures to fit into package tours: a fifteen-minute snippet of a ballet performed in Southern India; native handicrafts refashioned to fit oversize tour- ists. What is known is that tourism and travel is responsible for 5. 3 percent of the world’s carbon emissions and the degradation of nearly every tropical beach in the world.To make way for more resorts with spectacular views,developers destroy native habi- tats and ignore local concerns. (5) Preservationists decry the growing propensity to bulldoze old hotels and buildings in favor of constructing new resorts,water holes and entertain-ment spots that look identical whether in Singapore,Dubai or Johannesburg,a world where diversity is replaced with homogeneity. Another catastrophe for countries betting on tourism has come from wealthy vacationers who fall in love with a country and buy so many second houses that locals can no longer afford to live in their own towns and villages.

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During recent years we have heard much about “race”: how this race does certain things and that race believes certain things and so on. Yet, the (1 )phenomenon of race consists of a few surface indications.We judge race usually (2 ) the coloring of the skin: a white race,a brown race, a yellow race and a black race. But (3 )you were to remove the skin you could not (4 )anything about the race to which the individual belonged,There is (5 ) in physical struct ture, the brain or the internal organs to (6 ) a difference.There are four types of blood. (7 ) types are found in every race, and no type is distinct to any race. Human brains are the(8 )• No scientists could examine a brain and tell you the race to which the individual belonged. Brains will (9 ) in size, but this oc- curs within every race. (10 ) does size have anything to do with intelligence. The largest brain(11 )examined belonged to a person of weak (12)On the other hand, some of our most distinguished people have had (13 )brains.Mental tests which are reasonably (14 ) show no differences in intelligence between races. High and low test results both can be recorded by different members of any race.(15 ) equal educational advantages, there will be no difference in average standings, ei- ther on account of race or geographical location. Individuals of every race (16 )civilization to go backward or forward. Training and education can change the response of a group of people (17 )enable them to behave in a / an (18 ) way.The behavior and ideals of people change according to circumstances, but they can always go back or go on to something new(19 )is better and higher than anything (20 ) the past

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