unitforwantofadrinkPPT课件

1、1.when the word appears in the print nowadays, crisis is rarely far behind.(para. 1)Discussion of TextToday, whenever people mention the word water in books or newspapers, you know they are going to talk about water crisis.The opening paragraph summarizes what books and newspaper articles say about

2、the present water problem.In print: printed in book, newspaper, etc.Rarely far behind: very near.第1页/共35页2.Water, it is said, is the new oil: a resource long squandered, now growing expensive and soon to be overwhelmed by insatiable demand.(para. 1) Like oil, water, a natural resource, which has for

3、 a long time been stupidly wasted, is becoming an expensive commodity, and will soon be exhausted by the excessive consumption of humanity. Here the writer is reminding people of the Mideast Oil Crisis in the 1970s. In October 1973, Arab petroleum exporting countries cut off exports of petroleum to

4、many Western nations, including the United States, in response to their involvement in the Arab-Israeli conflicts. The embargo led to rising oil prices in the early 1970s, bringing widespread panic to western countries. Many people believe that high oil consumption in these countries was the root of

5、 the oil crisis. The Mideast Oil Crisis enhanced public environmental awareness and heightened public concern over natural resource scarcity.第2页/共35页The 1973 Arab Oil EmbargoOn Dec. 23, 1973, cars formed a double line at a gas station in New York City. The Arab oil embargo caused gas shortages natio

6、nwide and shaped U.S. foreign policy to this day.第3页/共35页3.Aquifers are falling, glaciers vanishing, reservoirs drying up and rivers no longer flowing to the sea.(para. 1)This sentence explains why the author believes that water is “ soon to be exhausted” by describing what is happening to major wat

7、er-holding parts of Earth including aquifers, glaciers, rivers(all naturally formed),and man-made reservoirs. The author uses accurate and specific verbs to show they are disappearing from our planet:(aquifers)falling:becoming lower(glaciers)vanishing:melting(reservoirs)drying up: becoming dry(river

8、s)no longer flowing to the sea:(sections of them)drying up so that they are no longer a continuous flow of water to the sea.第4页/共35页4.Climate change threatens to make the problem worse.(para. 1)Threaten:to be likely to harm or destroy sth, e.g.Global warming, which causes the seas to rise, threatens

9、 to engulf islands.The civil war is threatening to split the country. The countrys crippling debts could threaten its entire financial system.第5页/共35页5.Everyone must use less water if famine, pestilence and mass migration are not to sweep the globe.(para.1) All of us must use less water to avoid the

10、se disasters as famine, epidemic, and mass migration throughout the world.Mass migration: here referring to the movement of large numbers of people from one place or one part of world to another escape the disasters caused by shortage of waterNote: The concluding sentence suggests a simple solution

11、to the problem: use less water.第6页/共35页6.The language is often overblown, and the remedies sometimes ill-conceived, but the basic message is not wrong.(para. 2)The language used in these books and articles are often exaggerated, and the solutions suggested sometimes do not sound sensible(for example

12、, we may ask, “it is sensible to urge people to use less water when they want to maintain a comfortable lifestyle and live on a nutritious diets?”)Ill -conceived: not showing careful thought; not sounding sensibleThe basic message: the key idea that people should use less water第7页/共35页7.Bringing sup

13、ply and demand into equilibrium will be painful, and political disputes may increase in number and intensify in their capacity to cause trouble.(para. 2)It is extremely difficult to balance peoples demand for more water and the amount of water that is available.Bringing supply and demand into equili

14、brium:making demand match supply;not using more water than is availablePolitical disputes may increase in number:(there will be)more and more political disputes over waterIntensify in their capacity to cause trouble:(and these disputes)may cause more and more serious troubles 1.2.3.第8页/共35页8.To carr

15、y on with present practice would indeed be to invite disaster.(para. 2)If people maintain their present lifestyle and continue wasting water the way they do, they would head for disaster.This is a sentence of implied condition, which is conveyed in the subject “to carry no with present practice.”Inv

16、ite:to encourage sth bad to happen, esp. Without intending to e.g. The First Ladys recent trip invited sharp criticism. The mans behavior is inviting suspicion第9页/共35页9.Then the green revolution in an inspired combination of new crop breeds, fertilizers and water, made possible a huge rise in the po

17、pulation.(para. 3)The sentence lists the causes for a tremendous increase in the worlds food supply. First and foremost, improved methods of farming, then better breeds, and fertilizers. The consequence is a huge rise of the worlds population.The green revolution: a term widely used to describe the

18、effort to increase and diversify crop yields in agriculturally less advanced regions of the world/a large increase in the amount of crops, such as wheat or rice, that are produced because of improved scientific methods of farming The film is hailed as an inspired adaption of a bestseller. She is one

19、 of the few inspired teachers Ive ever seen.Inspired:extraordinarily good, brilliant and creativee.g.第10页/共35页点击添加标题10.Domestic activities take the other 8%(para. 5)Domestic activities:referring to sanitation, waste disposal, etc.11.One reason is that the amount of water is finite. (para. 6)One reas

20、on is that the amount of water available is limited.第11页/共35页12.The world will have no more of it in 2025 or 2050 than it has today, or when it lapped at the sides of Noahs Ark.(para. 6)In 2025 or 2050, the worlds water supply will be the same as it is today, or in the days of Noah.When it lapped at

21、 the sides of Noahs Ark: when flood water hit the sides of Noahs Ark in small wavesThe metaphor is used to emphasize the fact that worlds water supply has remained the same since ancient times.第12页/共35页 Four years later British chemist Joseph Priestley discovered that objects burned more brightly an

22、d rapidly in oxygen, another component of air. In 1772, British physician Daniel Rutherford isolated nitrogen from air and discovered that objects would not burn in it.13.The law of conservation of mass(para. 6) The law of conservation of mass states that, in a chemical reaction, the total amount of

23、 matter remains constant. The law of conservation of mass served as the cornerstone of 19th-century chemistry. Based on Priestleys discoveries, French chemist Antoine Lavoisier postulated that air was a mixture of oxygen and nitrogen and that only one-fifth of air was oxygen. He proposed that oxygen

24、 was the part of air that combined chemically with burning or rusting materials. Lavoisier also consolidated discoveries made in connection with gases into the law of conservation of mass. 第13页/共35页 Nature recycles water all the time. Water in oceans, lakes, and rivers evaporates, or turns into a ga

25、s and rises into the air. The water vapor eventually turn back into a liquid and falls as rain. The water cycle keeps the total amount of water on Earth the same.Water Cycle第14页/共35页14.The value of water as a commodity of course varies according to locality, purpose and circumstance.(para. 9)Vary: t

26、o change or be different according to the situation, e.g.A.Teaching methods should vary according to the topic.B.The ability to tolerate pain varies from person to person.C.Class size of elementary schools here varies between 35 and 40D.The price of a cut and blow-dry varies from $13.95 to $25.e.g.第

27、15页/共35页15.Scarce or plentiful, water is above all local.(para. 11)Whether there is little or a lot of it, most importantly, water is found in particular areas,not everywhere on Earth(not evenly distributed).Scarce or plentiful:a phrase functioning as a conditiona clauseA.All people, black or white,

28、 rich or poor, should live side by side.B. In wealth or in poverty, his wife proved a reliable anchor for his life.More Examples:第16页/共35页 .near the sea, the river water becomes less and less useful except to finally to sustain deltas, wetlands and to carry silt to sea. 16. . The opportunities dimin

29、ish to the point where it has no uses except to sustain deltas, wetlands and to carry silt out to sea.(para. 11) 17.as the demands of farmers have outgrown their supplies of rain and surface water.(para. 13).as the farmer need more fresh water than they can get from rivers, lakes and reservoirs as w

30、ell as rainfalls.Outgrow: to grow/increase faster than. e.g. Mankind is outgrowing food supplies. The citys migrant population has outgrown its public facilities. My granddaughter has outgrown all her clothes.第17页/共35页18. .the quantities being withdrawn exceed the annual recharge.(para. 13)Withdrawn

31、:(figurative use)to take water from below the surface of Earth(as you take money from your bank account)Exceed:to be greater than particular number or amount, Recharge:to refill (a battery) with electricity, here: to refill (the ground) with waterExamplesWhen deaths exceed births, the popular goes d

32、own.Income is expected to exceed expenditure.第18页/共35页19.deep-groundwater tables have dropped by up to 90meters.(para. 14)Water table: groundwater level, that is, the upper surface of groundwater, below which pores in the rocks are filled with water.第19页/共35页点击添加标题20.Part of the beauty of the boreho

33、le is that it requires no elaborate apparatus.(para. 15)Obtaining water out of the ground by drilling deep holes is easy, requiring no complicated equipment.The beauty of sth: an attractive, useful, or satisfying feature that makes sth esp. Suitable or useful,e.g. One of the beauties of microbloggin

34、g is that you can get your message to large numbers of people speedily.Part of the beauty of working at home is that you dont have to hurry to and from the workplace.Note:the choice between “part of beauty” and “one of the beauties” depends on whether you regard the word “beauty”as countable or unco

35、untable.Borehole: a deep hole drilled into the ground to obtain samples for geologic study or to release or extract water or oil.第20页/共35页 Tube well: a pipe with holes in the sides near the end, that is put into the ground and used with a pump operated by hand to bring water up from under the ground

36、21.A single farmer may be able sink his own tube well and start pumping.(para. 15)22.That is why India and China are now perforated with millions of irrigation wells, each drawing on the common resource. (para. 15)That is why millions of irrigated wells have been dug in India and China, both using t

37、he supply of water belonging to/shared by the whole community.第21页/共35页Perforate:to make a hole or holes in sth, or part of your body.In the road accident, his lung was perforated. She told her children not to wear earphones, for they can perforate their eardrums. Draw on sth: to use part of a suppl

38、y of sth that belongs to a group of people.E.g.第22页/共35页23.But even big aquifers are not immune to the laws of physics.(para. 15)Be immune to/ from sth: to be not influenced or affected by sth that happens or is doneNBA is not immune to economic recession.John seems to be immune to teasing.Examples:

39、第23页/共35页 Will: used to indicate the way that sth usu. Happens.24.But almost nowhere will the price reflect scarcity.(para. 15)Many countries are faced with the problem of water shortage, but the resource is free almost everywhere. Its low price does not show the scarcity of it.Here, the writer is a

40、dvocating treating resource as a commodity, the price of which is determined by supply and demand. This can help control and manage the stuff.第24页/共35页25.Price or not, water is certainly valued, and that value depends on the use to which it is harnessed.(para. 16)Whether it is reasonably price or no

41、t, water is a valuable resource, and the value is determined by the purpose it is made to serve.Price or not: another pattern of condensed conditional clauses introduced by “whether” Believe it or not, a 10-year-old girl beat a professional at chess. Like it or not, learners of English have to live

42、with its irregular spelling.More examples:第25页/共35页.The farmer harnessed two oxen to the plow.But here, “harness”is used figurativelye.g.In some areas, the poor feel harnessed to their jobs.“harness” also means “ to gain control of sth and use it for some purpose” e.g.The windmill is an example of h

43、ow people harness the wind to produce electricity.Harness:to attach a horse other animal to sth with harness第26页/共35页 .and no other stuff can replace water.26. And for this there is no substitute.(para. 17)27.No one survived in the ruins of Port-au-Prince for more than a few days after Januarys Eart

44、hquake unless they had access to some water-based food or drink.(para. 17)in the ruins of Port-au-Prince: in the completely damaged city of Port-au-PrinceJanuarys Earthquake: referring to the earthquake that struck Port-au-Prince, on 12 January 2010, devastating the cityhad access to some water-base

45、d food or drink: had some food or drink, of which water is the main ingredient第27页/共35页-based: a suffix used to form adjectives describing the basic part or feature of sth e.g. a pork-based fish carbon-based fuels a computer-based testing a rice-based dieta cream-based saucecommunity-based service第2

46、8页/共35页28.many people believe water to be a human right, a necessity more basic than bread or a roof over the head.(para. 17).many people believe that water is a right every human being is entitled to. It is a necessity more important than food and shelter(for water is infinite, and has no substitute).A human right: it refers to one of the basic right that many societies think every person should have. The right to life itself and the basic necessities of foo