Oil Prices, Exhaustible Resources, and Economic Growth

NBER WORKING PAPER SERIES

OIL PRICES, EXHAUSTIBLE RESOURCES, AND ECONOMIC GROWTH

James D. Hamilton

Working Paper 17759

https://www.wendangku.net/doc/7717807520.html,/papers/w17759

NATIONAL BUREAU OF ECONOMIC RESEARCH

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January 2012

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Oil Prices, Exhaustible Resources, and Economic Growth

James D. Hamilton

NBER Working Paper No. 17759

January 2012

JEL No. O40,Q30,Q41,Q43

ABSTRACT

This paper explores details behind the phenomenal increase in global crude oil production over the last century and a half and the implications if that trend should be reversed. I document that a key feature of the growth in production has been exploitation of new geographic areas rather than application of better technology to existing sources, and suggest that the end of that era could come soon. The economic dislocations that historically followed temporary oil supply disruptions are reviewed, and the possible implications of that experience for what the transition era could look like are explored. James D. Hamilton

Department of Economics, 0508

University of California, San Diego

9500 Gilman Drive

La Jolla, CA 92093-0508

and NBER

jhamilton@https://www.wendangku.net/doc/7717807520.html,

1Oil prices and the economics of resource exhaustion. One of the most elegant theories in economics is Hotelling’s(1931)characterization of the price of an exhaustible natural resource.From the perspective of overall social welfare, production today needs to be balanced against the consideration that,once consumed,the resource will be unavailable to future generations.One option for society would be to produce more of the commodity today,invest the current marginal bene?ts net of extraction costs in some other form of productive capital,and thereby accumulate bene?ts over time at the rate of interest earned on productive capital.An alternative is to save the resource so it can be used in the future.Optimal use of the resource over time calls for equating these two returns.This socially optimal plan could be implemented in a competitive equilibrium if the price of the resource net of marginal production cost rises at the rate of interest.For such a price path,the owner of the mine is just indi?erent between extracting a little bit more of the resource today or leaving it in the ground to be exploited at higher pro?t in the future.

This theory is compelling and elegant,but very hard to reconcile with the observed behavior of prices over the?rst century and a half of the oil industry.Figure1plots the real price of crude petroleum since1860.Oil has never been as costly as it was at the birth of the industry.Prior to Edwin Drake’s?rst oil well in Pennsylvania in1859,people were getting illuminants using very expensive methods.1The term kerosene,which we still use today to refer to a re?ned petroleum product,was actually a brand name used in the1850s for a liquid manufactured from asphalt or coal,a process which was then,as it still is now,

quite expensive.2Derrick’s Handbook(1898)reported that Drake had no trouble selling all the oil his well could produce in1859at a price of$20/barrel.Given the24-fold increase in estimates of consumer prices since1859,that would correspond to a price in2010dollars a little below$500/barrel.As drillers producing the new-found“rock oil”from other wells brought more of the product to the market,the price quickly fell,averaging$9.31/barrel for 1860(the?rst year shown in Figure1).In2010prices,that corresponds to$232a barrel, still far above anything seen subsequently.Even ignoring the initial half-century of the industry,the price of oil in real terms continued to drop from1900to1970.And despite episodes of higher prices in the1970s and2000s,throughout the period from1992-1999,the price of oil in real terms remained below the level reached in1920.

There are two traditional explanations for why Hotelling’s theory appears to be at odds with the long-run behavior of crude oil prices.The?rst is that although oil is in principle an exhaustible resource,in practice the supply has always been perceived to be so vast, and the date at which it will?nally be exhausted has been thought to be so far into the future,that?niteness of the resource had essentially no relevance for the current price.This interpretation could be reconciled with the Hotelling solution if one hypothesizes a tiny rent accruing to owners of the resource that indeed does grow at the rate of interest,but in practice has always been su?ciently small that the observed price is practically the same as the marginal extraction cost.

A second e?ort to save Hotelling’s theory appeals to the role of technological progress, which could lower marginal extraction costs(e.g.,Slade,1982),lead to discovery of new?elds

(Dasgupta and Heal,1979;Arrow and Chang,1982),or allow the exploitation of resources previously thought not to be economically accessible(Pindyck,1978).In generalizations of the Hotelling formulation,these can give rise to episodes or long periods in which the real price of oil is observed to fall,although eventually the price would begin to rise according to these models.Krautkraemer(1998)has a nice survey of theories of this type and examination of their empirical success at?tting the observed data.

Although it can sometimes be helpful to think about technological progress in broad, abstract terms,there is also much insight to be had from looking in some detail at the speci?c factors that allowed global oil production to increase almost without interruption over the last150years.For this purpose,I begin by examining some of the long-run trends in U.S.oil production.

1.1Oil production in the United States,1859-2010.

Certainly the technology for extracting oil from beneath the earth’s surface has evolved profoundly over time.Although Drake’s original well was steam-powered,some of the early drills were driven through rock by foot power,such as the spring-pole method.The workers would kick a heavy bit at the end of the rope down into the rock,and spring action from the compressed pole would lift the bit back up.After some time at this,the drill would be lifted out and a bucket lowered to bail out the debris.Of course subsequent years produced rapid advances over these?rst primitive e?orts—better sources of power, improved casing technology,and vastly superior knowledge of where oil might be found.

Other key innovations included the adoption of rotary drilling at the turn of the century, in which circulating?uid lifted debris out of the hole,and secondary recovery methods?rst developed in the1920s,in which water,air,or gas is injected into oil wells to repressurize the reservoir and allow more of the oil to be lifted to the surface.

Figure2plots the annual oil production levels for Pennsylvania and New York,where the industry began,from1862to2010.Production increased by a factor of10between 1862and1891.However,it is a mistake to view this as the result of application of better technology to the initially exploited?elds.Production from the original Oil Creek District in fact peaked in1874(Williamson and Daum,1959,p.378).The production gains instead came primarily from development of new?elds,most importantly the Bradford?eld near the Pennsylvania-New York border,but also from Butler,Clarion,and Armstrong Counties. Nevertheless,it is unquestionably the case that better drilling techniques than used in Oil Creek were necessary in order to reach the greater depths of the Bradford formation.

One also sees quite clearly in Figure2the bene?ts of the secondary recovery methods applied in the1920s,which succeeded in producing much additional oil from the Bradford formation and elsewhere in the state.However,it is worth noting that these methods never lifted production in Pennsylvania back to where it had been in1891.In2010—with the truly awesome technological advances of the century and a half since the industry began, and with the price of oil5times as high(in real terms)as it had been in1891—Pennsylvania and New York produced under4million barrels of crude oil.That’s only12%of what had been produced in1891—120years ago—and about the level that the sturdy farmers with

their spring-poles were getting out of the ground back in1868.

Although Pennsylvania was the most important source of U.S.oil production in the 19th century,the nation’s oil production continued to increase even after Pennsylvanian production peaked in1891.The reason is that later in the century,new sources of oil were also being obtained from neighboring West Virginia and Ohio(see Figure3).Production from these two states was rising rapidly even as production from Pennsylvania and New York started to fall.Ohio production would continue to rise before peaking in1896,and West Virginia did not peak until1900.

These four states together accounted for90%of U.S.production in1896,with the peak in production from the region as a whole coming that year(see Figure4).Overall U.S.pro-duction declined for a few years with falling supplies from Appalachia,but quickly returned to establishing new highs in1900,thanks to growth in production from new areas in the central United States,details of which are shown in Figure5.Note the di?erence in scale, with the vertical axes in Figure5spanning6times the magnitude of corresponding axes in Figure3.Each of the regions featured in Figure5would eventually produce far more oil than Appalachia ever did.These areas began producing much later than Appalachia,and each peaked much later than Appalachia.The combined production of Illinois and Indiana peaked in1940,Kansas-Nebraska in1957,the southwest in1960,and Wyoming in1970.

Far more important for U.S.total production were the four states shown in Figure6, which uses a vertical scale2.5times that for Figure5.California,Oklahoma,Texas,and Louisiana account for70%of all the oil ever produced in the United States.Production

from Oklahoma reached a peak in1927,though it was still able to produce at80%of that level as recently as1970before entering a modern phase of decline that now leaves it at25% of the1927production levels.Texas managed to grow its oil production until1972,and today produces about a third of what it did then.California production continued to grow until1985before peaking.The graph for Louisiana(bottom panel of Figure6)includes all the U.S.production from the Gulf of Mexico,growing production from which helped bring the state’s indicated production for2010up to a value only33%below its peak in1971.

Figure7plots production histories for the two regions whose development began latest in U.S.history.Production from Alaska peaked in1988.North Dakota is the only state that continues to set all-time records for production,thanks in part to use of new drilling techniques for recovering oil from shale formations.To put the new Williston Basin produc-tion in perspective,the138million barrels produced in North Dakota and Montana in2010 is about half of what the state of Oklahoma produced in1927and a?fth of what the state of Alaska produced in1988.However,the potential for these?elds looks very promising and further signi?cant increases from2010levels seems assured.

The experience for the U.S.thus admits a quite clear summary.Production from every state has followed a pattern of initial increase followed by eventual decline.The feature that nonetheless allowed the total production for the U.S.to exhibit a seemingly uninterrupted upward trend over the course of a century was the fact that new,more promising areas were always coming into production at the same time that mature?elds were dying out(see Figure8).Total U.S.production continued to grow before peaking in1970,long after the

original?elds in Appalachia and the central U.S.were well into decline.

And the decline in production from both individual regions within the U.S.as well as the United States as a whole has come despite phenomenal improvements in technology over time.Production from the Gulf of Mexico has made a very important contribution to slowing the rate of decline over the most recent decade.Some of this production today is coming from wells that begin a mile below sea level and bore from there through up to a half-dozen more miles of rock—try doing that with three guys kicking a spring-pole down!The decline in U.S.production has further come despite aggressive drilling in very challenging environments and widespread adoption of secondary and now tertiary recovery methods.The rise and fall of production from individual states seems much more closely related to discoveries of new?elds and their eventual depletion than to the sorts of price incentives or technological innovations on which economists are accustomed to focus.

Notwithstanding,technological improvements continue to bring signi?cant new?elds into play.The most important recent development has been horizontal rather than verti-cal drilling through hydrocarbon-bearing formations accompanied by injection of?uids to induce small fractures in the rock.These methods have allowed access to hydrocarbons trapped in rock whose permeability or depth prevented removal using traditional methods. The new methods have enabled phenomenal increases in supplies of natural gas as well as signi?cant new oil production in areas such as North Dakota and Texas.Wickstrom,et.al. (2011)speculated that application of hydraulic fracturing to the Utica Shale formation in Ohio might eventually produce several billion barrels of oil,which would be more than the

cumulative production from the state up to this point.If that indeed turns out to be the case,it could lead to a third peak in the graphs in Figure3for the Appalachian region that exceeds either of the?rst two,though for comparison the projected lifetime output from Utica would still only correspond to a few years of production from Texas at that state’s peak.

Obviously price incentives and technological innovations matter a great deal.More oil will be brought to the surface at a price of$100a barrel than at$10a barrel,and more oil can be produced with the new technology than with the old.But it seems a mistake to overstate the operative elasticities.By1960,the real price of oil had fallen to a level that was1/3its value in1900.Over the same period,U.S.production of crude oil grew to become55times what it had been in1900.On the other hand,the real price of oil rose8-fold from1970to2010,while U.S.production of oil fell by43%over those same40 years.The increase in production from1900to1960thus could in no way be attributed to the response to price incentives.Likewise,neither huge price incentives nor impressive technological improvements were su?cient to prevent the decline in production from1970to 2010.Further exploitation of o?shore or deep shale resources may help put U.S.production back on an upward trend for the next decade,but it seems unlikely ever again to reach the levels seen in1970.

1.2W orld oil production,1973-2010.

Despite the peak in U.S.production in1970,world oil production was to grow to a level in 2010that is60%higher than it had been in1970.The mechanics of this growth are the same as allowed total U.S.production to continue to increase long after production from the initial areas entered into decline—increases from new?elds in other countries more than o?set the declines from the United States.For example,the North Sea and Mexico accounted for only1%of world production in1970,but had grown to13%of total world output by1999. But production from the North Sea peaked in that year,and in2010is only at54%of the peak level(see Figure9).Cantarell,which is Mexico’s main producing?eld,also appears to have passed peak production,with the country now at75%of its2004oil production.

Production from members of the Organization of Petroleum Exporting Countries(OPEC) must be interpreted from a much di?erent perspective.The episodes of declining production one sees in the bottom panel of Figure10have little to do with geological depletion but instead often re?ect dramatic geopolitical events such as the OPEC embargo of1973-74, the Iranian revolution in1978-1979,the Iranian revolution and beginning of the Iran-Iraq War1978-1981,and the?rst Persian Gulf war in1990-91,events that will be reviewed in more detail in the following section.In addition,Saudi Arabia in particular(top panel)has often made a deliberate decision to increase or decrease production in an e?ort to mitigate price increases or decreases.For example,Saudi Arabia cut production to try to hold up prices during the weak oil market1981-85and recession of2001,and boosted production to make up for output lost from other producing countries during the two Persian Gulf

wars.However,the decline in Saudi Arabian production since2005would have to be attributed to di?erent considerations from those that explain the earlier historical data.The kingdom’s magni?cent Ghawar?eld has been in production since1951,and in recent years had accounted for perhaps6%of total world production all by itself.There is considerable speculation that Ghawar may have peaked,though this is di?cult to con?rm.What we do know is that,for whatever reason,Saudi Arabia produced600,000fewer barrels each day in 2010than it did in2005,and with growing Saudi consumption of their own oil,the drop in exports from Saudi Arabia has been even more dramatic.

A mix of factors has clearly also contributed to stagnating production from other OPEC members over the last5years.Promising new?elds in Angola have allowed that country to double its production since2003.In Nigeria and Iraq,con?icts and unrest have held back what appears to be promising geological potential.In Venezuela and Iran,it is hard to know how much more might be produced with better functioning governments.But again, although there is a complicated mix of di?erent factors at work in di?erent countries,the bottom line is that the total production from OPEC has essentially been?at since2005.

At the same time,some other countries continue to register increases in oil production (see Figure11).China has doubled its oil production since1982,though its three most important?elds(Daqing,Shengli,and Liaohe)peaked in the mid1990s(Kambara and Howe,2007).Canadian oil production continues to increase as a result of the contribution of oil sands.Unfortunately,exploitation of this resource is far more costly in terms of capital and energy inputs and environmental externalities relative to conventional sources,

and it is di?cult to see it ever accounting for a major fraction of total world oil production. Other regions such as Brazil,central Asia,and Africa have also seen signi?cant gains in oil production(bottom panel of Figure11).Overall,global production of oil from all sources was essentially constant from2005to2010(see Figure12).

1.3Reconciling historical experience with the theory of exhaustible

resources.

The evidence from the preceding subsections can be summarized as follows.When one looks at individual oil-producing regions,one does not see a pattern of continuing increases as a result of ongoing technological progress.Instead there has inevitably been an initial gain as key new?elds were developed followed by subsequent decline.Technological progress and the incentives of higher prices can temporarily reverse that decline,as was seen for example in the impressive resurgence of Pennsylvanian production in the1920s.In recent years these same factors have allowed U.S.production to grow rather than decline,and that trend in the U.S.may continue for some time.However,these factors have historically appeared to be distinctly secondary to the broad reality that after a certain period of exploitation,annual ?ow rates of production from a given area are going to start to decline.Those encouraged by the10%increase in U.S.oil production between2008and2010should remember that the level of U.S.production in2010is still25%below where it had been in1990(when the real price of oil was half of what it is today)and43%below the level of1970(when the real price of oil was1/8of what it is today).

Some may argue that the peaking of production from individual areas is governed by quite di?erent economic considerations than would apply to the?nal peaking of total production from all world sources combined.Certainly in an environment in which the market is pricing oil as an essentially inexhaustible resource,the pattern of peaking documented extensively above is perfectly understandable,given that so far there have always been enough new ?elds somewhere in the world to take the place of declining production from mature regions. One could also reason that,even if the price of oil has historically been following some kind of Hotelling path,?elds with di?erent marginal extraction costs would logically be developed at di?erent times.Smith(2011)further noted that,according to the Hotelling model,the date at which global production peaks would be determined endogenously by the cumulative amount that could eventually be extracted and the projected time path for the demand function.His analysis suggests that the date for an eventual peak in global oil production should be determined by these economic considerations rather than the engineering mechanics that have produced the historical record for individual regions detailed above.

However,my reading of the historical evidence is as follows.(1)For much of the history of the industry,oil has been priced essentially as if it were an inexhaustible resource.(2) Although technological progress and enhanced recovery techniques can temporarily boost production?ows from mature?elds,it is not reasonable to view these factors as the primary determinants of annual production rates from a given?eld.(3)The historical source of increasing global oil production is exploitation of new geographical areas,a process whose

promise at the global level is obviously limited.The combined implication of these three observations is that,at some point there will need to be a shift in how the price of oil is determined,with considerations of resource exhaustion playing a bigger role than they have historically.

A factor accelerating the date of that transition is the phenomenal growth of demand for oil from the emerging economies.Eight emerging economies—Brazil,China,Hong Kong, India,Singapore,South Korea,Taiwan,and Thailand—accounted for43%of the increase in world petroleum consumption between1998and2005and for135%of the increase between 2005and2010(the rest of the world decreased its petroleum consumption over the latter period in response to the big increase in price).3And,as Hamilton(2009a)noted,one could easily imagine the growth in demand from the emerging economies continuing.One has only to compare China’s one passenger vehicle per30residents today with the one vehicle per1.3residents seen in the United States,or China’s2010annual petroleum consumption of2.5barrels per person with Mexico’s6.7or the United States’22.4.Even if the world sees phenomenal success in?nding new sources of oil over the next decade,it could prove quite challenging to keep up with both depletion from mature?elds and rapid growth in demand from the emerging economies,another reason to conclude that the era in which petroleum is regarded as an essentially unlimited resource has now ended.

Some might infer that the decrease in Saudi Arabian production since2005re?ects not an inability to maintain production?ows from the mature Ghawar?eld but instead is a deliberate response to recognition of a growing importance of the scarcity rent.For example,

Hamilton(2009a)noted the following story on April13,2008from Reuters news service: Saudi Arabia’s King Abdullah said he had ordered some new oil discoveries left

untapped to preserve oil wealth in the world’s top exporter for future generations,

the o?cial Saudi Press Agency(SPA)reported.

“I keep no secret from you that when there were some new?nds,I told them,

‘no,leave it in the ground,with grace from God,our children need it’,”King

Abdullah said in remarks made late on Saturday,SPA said.

If that is indeed the interpretation,it is curious that we would see the private optimizing choices predicted by Hotelling manifest by sovereign governments rather than the?elds under control of private oil companies.In any case,it must be acknowledged that calculation of the correct Hotelling price is almost insurmountably di?cult.It is hard enough for the best forecasters accurately to predict supply and demand for the coming year.But the critical calculation required by Hotelling is to evaluate the transversality condition that the resource be exhausted when the price reaches that of a backstop technology or alternatively over the in?nite time horizon if no such backstop exists.That calculation is orders of magnitudes more di?cult than the seemingly simpler task of just predicting next year’s supply and demand.

One could argue that the combined decisions of the many participants in world oil markets can make a better determination of what the answer to the above calculation should be than can any individual,meaning that if the current price seems inconsistent with a scenario in which global oil production will soon reach a peak,then such a scenario is perhaps not

the most likely outcome.But saying that the implicit judgment from the market is the best guess available is not the same thing as saying that this guess is going to prove to be correct.The historical record surely dictates that we take seriously the possibility that the world could soon reach a point from which a continuous decline in the annual?ow rate of production could not be avoided,and inquire whether the transition to a pricing path consistent with that reality could prove to be a fairly jarring event.For this reason,it seems worthwhile to review the historical record on the economic response to previous episodes in which the price or supply of oil changed dramatically,to which we now turn in the next section.

2Oil prices and economic growth.

2.1Historical oil price shocks.

There have been a number of episodes over the last half century in which con?icts in the Middle East have led to signi?cant disruptions in production of crude oil.These include closure of the Suez Canal following the con?ict between Egypt,Israel,Britain,and France in October1956,the oil embargo implemented by the Arab members of OPEC following the Arab-Israeli War in October1973,the Iranian revolution beginning in November1978,the Iran-Iraq War beginning in September of1980,and the?rst Persian Gulf war beginning in August1990.Figure13summarizes the consequences of these5events for world oil supplies. In each panel,the solid line displays the drop in production from the a?ected areas expressed

as a percentage of total world production prior to the crisis.In each episode,there were some o?setting increases in production elsewhere in the world.The dashed lines in Figure 13indicate the magnitude of the actual decline in total global production following each event,again expressed as a fraction of world production.Each of these5episodes was followed by a decrease in world oil production of4-9%.

There have also been some other more minor supply disruptions over this period.These include the combined e?ects of the second Persian Gulf war and strikes in Venezuela be-ginning in December2002,and the Libyan revolution in February2011.The disruption in supply associated with either of these episodes was about2%of total global production at the time,or less than a third the size of the average event in Figure13.

There are other episodes since World War II when the price of oil rose abruptly in the absence of a signi?cant physical disruption in the supply of oil.Most notable of these would be the broad upswing in the price of oil beginning in2004,which accelerated sharply in 2007.The principal cause of this oil spike appears to have been strong demand for oil from the emerging economies confronting the stagnating global production levels documented in the previous sections(see Kilian,2008,2009,Hamilton,2009b and Kilian and Hicks,2011). Less dramatic price increases followed the economic recovery from the East Asian Crisis in1997,dislocations associated with post World War II growth in1947,and the Korean con?ict in1952-53.Table1summarizes a series of historical episodes discussed in Hamilton (forthcoming[b]).It is interesting that of the11episodes listed,10of these were followed by a recession in the United States.The recession of1960is the only U.S.postwar recession

that was not preceded by a spike in the price of crude oil.

A large empirical literature has investigated the connection between oil prices and real economic growth.Early studies documenting a statistically signi?cant negative correlation include Rasche and Tatom(1977,1981)and Santini(1985).Empirical analysis of dynamic forecasting regressions found that oil price changes could help improve forecasts of U.S.real output growth(Hamilton,1983;Burbidge and Harrison,1984;Gisser and Goodwin,1986). However,these speci?cations,which were based on linear relations between the log change in oil prices and the log of real output growth,broke down when the dramatic oil price decreases of the mid-1980s were not followed by an economic boom.On the contrary,the mid-1980s appeared to be associated with recession conditions in the oil-producing states(Hamilton and Owyang,forthcoming).Mork(1989)found a much better?t to a model that allowed for oil price decreases to have a di?erent e?ect on the economy from oil price increases,though Hooker(1996)demonstrated that this modi?cation still had trouble describing subsequent data.Other papers?nding a signi?cant connection between oil price increases and poor economic performance include Santini(1992,1994),Rotemberg and Woodford(1996),Daniel (1997),and Carruth,Hooker and Oswald(1998).

Alternative nonlinear dynamic relations seem to have a signi?cantly better?t to U.S. data than Mork’s simple asymmetric formulation.Loungani(1986)and Davis(1987a, 1987b)found that oil price decreases could actually reduce economic growth,consistent with the claim that sectorial reallocations could be an important part of the economic transmission mechanism resulting from changes in oil prices in either direction.Ferderer

(1996),Elder and Serletis(2010),and Jo(2011)showed that an increase in oil price volatility itself tends to predict slower GDP growth,while Lee,Ni,and Ratti(1995)found that oil price increases seem to a?ect the economy less if they occur following an episode of high volatility.Hamilton(2003)estimated a?exible nonlinear form and found evidence for a threshold e?ect,in which an oil price increase that simply reverses a previous decrease seems to have little e?ect on the economy.Hamilton(1996),Raymond and Rich(1997),Davis and Haltiwanger(2001)and Balke,Brown and Yücel(2002)produced evidence in support of related speci?cations,while Carlton(2010)and Ravazzolo and Rothman(2010)reported that the Hamilton(2003)speci?cation performed well in an out-of-sample forecasting exercise using data as it would have been available in real time.Kilian and Vigfusson(forthcoming [a])found weaker(though still statistically signi?cant)evidence of nonlinearity than reported by other researchers.Hamilton(forthcoming[a])attributed their weaker evidence to use of a shorter data set and changes in speci?cation from other researchers.

A negative e?ect of oil prices on real output has also been reported for a number of other countries,particularly when nonlinear functional forms have been employed.Mork,Olsen and Mysen(1994)found that oil price increases were followed by reductions in real GDP growth in6of the7OECD countries investigated,the one exception being the oil exporter Norway.Cu?ado and Pérez de Gracia(2003)found a negative correlation between oil prices changes and industrial production growth rates in13out of14European economies,with a nonlinear function of oil prices making a statistically signi?cant contribution to forecast growth rates for11of these.Jiménez-Rodríguez and Sánchez(2005)found a statistically

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17. I can't do this. 我不能这么做。 18. Let me explain why I was late. 让我解释迟到的理由。 19. Let's have a beer or something. 咱们喝点啤酒什么的。 20. Where is your office? 你们的办公室在哪? 21. What is your plan? 你的计划是什么? 22. When is the store closing? 这家店什么时候结束营业? 23. Are you sure you can come by at nine? 你肯定你九点能来吗? 24. Am I allowed to stay out past 10? 我可以十点过后再回家吗? 25. The meeting was scheduled for two hours, but it is not over yet. 会议原定了两个小时，不过现在还没有结束。 26. Tom's birthday is this week. 汤姆的生日就在这个星期。 27. Would you care to sit down for a while? 你要不要坐一会呢? 28. Can you cover for me on Friday? 星期五能不能请你替我个班? 29. Could you do me a big favor? 能否请你帮我个忙? 30. He is crazy about Friends. 他对《老友记》很着迷。 31. Can you imagine how much he paid for that car?你能想象他买那车花了多少钱吗?

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[解析] 这是破冰的一种非常好的方式。当你对某件事情或者某人的境遇特别好奇的时候，可以用上这句话。 6. Are you all right? [翻译] 你还好吧？ [解析] 生活中总有磕磕绊绊，当你看到别人眉头紧皱，或者面色难看时，可以用这句话进行询问。另外，all right在英国很多时候表示go ahead. 7. Give me a book please, Jane. [翻译] 简，请递给我一本书。 [解析] 非常简单的句子，在图书馆，教室请别人递给自己东西时脱口而出。 8. There is a refrigerator in the kitchen. [翻译] 在厨房里有一个冰箱。 [解析] 在给别人介绍自己家的物品或者某处风景的时候，都可以用上。 9. Where is it? [翻译] 在哪？ [解析] 可以直接用where来提问。 10. What must I do? [翻译] 有什么必须要做的？

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这50个万能句型帮你快速提升英语口语！ 1.May I…? 我可以……吗？ 常用句子：May I come in? 我可以进来吗？ May I help you? 您需要帮忙吗？ May I ask you a question? 我可以问你一个问题吗？ 搭配：接动词原型。 例句：May I speak to Vincent? 请问文森在吗？ May I use your telephone? 我可以借用你的电话吗？ May I have a seat?

我可以坐下吗？ 功能: 用这些话显得很有教养。 2. Can you …? 你能……吗？ 常用句子：Can you help me? 你能帮帮我吗？ Can you do me a favor? 你能帮我个忙吗？ Can you please tell me where is the bus stop? 你能告诉我公共汽车站怎么走吗？ 搭配：接动词原型。 例句：Can you please shut the door? 你能把门关上吗？ Can you translate the sentence into Chinese for me? 你能帮我把这个句子翻译成中文吗？

Can you lend me some money? 你能借我点钱吗？ 功能：用于比较熟悉的人之间，会让对方感觉亲切。如果想再客 气一点，可以把can换成could。 3. I’d like to … 我想…… 常用句子：I’d like to have a self-introduction. 我想作个自我介绍。 I’d like to talk about the matter. 我想谈谈那件事。 I’d like to have a cup of tea. 我想喝杯茶。 搭配：加动词原型。 例句：I’d like to book a double-room. 我想订一间双人房。