Unit 5 For want of a drink

1、精选ppt1For want of a water精选ppt21.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 an

2、d newspaper articles say about the present water problem.In print: printed in book, newspaper, etc.Rarely far behind: very near.精选ppt32.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 na

3、tural resource, which has for 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

4、 off exports of petroleum to 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 th

5、ese countries was the root of the oil crisis. The Mideast Oil Crisis enhanced public environmental awareness and heightened public concern over natural resource scarcity.精选ppt4The 1973 Arab Oil EmbargoOn Dec. 23, 1973, cars formed a double line at a gas station in New York City. The Arab oil embargo

6、 caused gas shortages nationwide and shaped U.S. foreign policy to this day.精选ppt53.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

7、is happening to major water-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)dryi

8、ng up: becoming dry(rivers)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.精选ppt64.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

9、seas to rise, threatens to engulf islands.The civil war is threatening to split the country. The countrys crippling debts could threaten its entire financial system.精选ppt75.Everyone must use less water if famine, pestilence and mass migration are not to sweep the globe.(para.1) All of us must use le

10、ss water to avoid these 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 sugges

11、ts a simple solution to the problem: use less water.精选ppt86.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 s

12、ensible(for example, 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精选p

13、pt97.Bringing supply 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 d

14、emand into equilibrium: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.

15、精选ppt108.To carry 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 prese

16、nt practice.”Invite: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精选ppt119.Then the green revolution in an inspired combination of new crop breeds, fertilizers and water, made possible a huge

17、 rise in the population.(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 t

18、o describe the 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 bestsel

19、ler. She is one of the few inspired teachers Ive ever seen.Inspired:extraordinarily good, brilliant and creativee.g.精选ppt12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. (par

20、a. 6)One reason is that the amount of water available is limited.精选ppt1312.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 i

21、t lapped at 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.精选ppt14 Four years later British chemist Joseph Priestley discovered that objects burned more br

22、ightly and 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

23、amount of 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 th

24、at oxygen 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. 精选ppt15 Nature recycles water all the time. Water in oceans, lakes, and rivers evaporates, or turns in

25、to a gas 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精选ppt1614.The value of water as a commodity of course varies according to locality, purpose and circumstance.(para. 9)Va

26、ry: to 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.

27、e.g.精选ppt1715.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 whi

28、te, 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:精选ppt18 .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 dimi

29、nish 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

30、well 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.精选ppt1918. .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 do

32、wn.Income is expected to exceed expenditure.精选ppt2019.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.精选ppt21点击添加标题20.Part of the beauty of the borehole is

33、 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 microblogging is

34、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 uncountab

35、le.Borehole: a deep hole drilled into the ground to obtain samples for geologic study or to release or extract water or oil.精选ppt22 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 ground21.A si

36、ngle 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 the supp

37、ly of water belonging to/shared by the whole community.精选ppt23Perforate: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 supply of sth

38、that belongs to a group of people.E.g.精选ppt2423.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:精选ppt25 Wil

39、l: 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 advocating tre

40、ating resource as a commodity, the price of which is determined by supply and demand. This can help control and manage the stuff.精选ppt2625.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 not, water is a v

41、aluable 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 with its irregu

42、lar spelling.More examples:精选ppt27e.g.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 how people harn

43、ess the wind to produce electricity.Harness:to attach a horse other animal to sth with harness精选ppt28 .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 Earthquake unless th

44、ey 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-based food or drink:

45、 had some food or drink, of which water is the main ingredient精选ppt29-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精选ppt3028.many peopl

46、e 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 t