Information on past climates is ofprimaryrelevancetoarchaeologybecause of what it tells us about the effects on the land and on the resources that people needed tosurvive. The mostcrucialeffect ofclimatewas on thesheerquantityof landavailablein each period, measurable by studyingancientcoastlines. These have changedconstantlythroughtime, even inrelativelyrecent periods, as can be seen from theNeolithicstone circle of Er Lannic, in Brittany, France (once inland but now half submerged on an island) ormedievalvillages in east Yorkshire, England, that have tumbled into the sea in the last few centuries as the North Sea gnaws its way westward and erodes the cliffs. Conversely, silts deposited by rivers sometimes push the sea farther back, creating new land, as at Ephesus in westernTurkey, a port on thecoastin Roman times but today some five kilometers inland.

Nevertheless, for archeologists concerned with the long periods of time of thePaleolithicperiod, there are variations in coastlines of much greatermagnitudetoconsider. Theexpansionand contraction of thecontinentalglaciers caused huge andunevenrises and falls in sea levels worldwide. When the ice sheets grew, the sealevelwoulddropas water became locked up in the glaciers; when the ice melted, the sealevelwould rise again. Falls in sealeveloftenexposeda number of important land bridges, such as those linking Alaska to northeast Asia and Britain to northwest Europe, aphenomenonwith far-reaching effects not only on humancolonizationof the globe but also on the environment as a whole - thefloraandfaunaofisolatedor insular areas wereradicallyand often irreversibly affected. Between Alaska and Asia today lies the Bering Strait, which is soshallowthat a fall in sealevelof only four meters would turn it into a land bridge. When the ice sheets were at their greatestextentsome 18,000 years ago (theglaciermaximum), it is thought that the fall was about 120 meters, whichthereforecreated not merely a bridge but avastplain,1,000 kilometers from the north to the south, which has been called Beringia. Theexistenceof Beringia (and theextentto which it could have supported human life) is one of thecrucialpieces ofevidencein the continuingdebateabout the likelyrouteand date of humancolonizationof the New World.

The assessment of past rises and falls in sealevelrequires study of submerged land surfaces off thecoastand of raised or elevated beaches on land. Raised beaches are remnants offormercoastlines at higher levelsrelativeto the present shoreline andvisible, forinstance, along the Californiancoastnorth of San Francisco. The height of a raisedbeachabove the present shoreline, however, does not generally give astraightforwardindicationof the height of aformersealevel. In themajorityof cases, the beaches lie at a higherlevelbecause the land has been raised upthroughisostatic uplift ortectonicmovement. Isostatic uplift of the land occurs when the weight of ice is removed as temperatures rise, as at the end of an ice age; it has affected coastlines, for example, in Scandinavia, Scotland, Alaska, and Newfoundland during thepostglacialperiod. Tectonicmovements involve displacements in the plates that make up Earth’scrust. Middle and LatePleistoceneraised beaches in theMediterraneanare oneinstanceof such movements.

Raised beaches oftenconsistof areas of sand, pebbles, or dunes, sometimes containing seashells or piles ofdebriscomprising shells and bones ofmarineanimals used by humans. In Tokyo Bay, for example,shellmounds of the Jomon period (about 10,000 to 300 B.C.E.)mark thepositionof the shoreline at a time ofmaximuminundationby the sea (6,500-5,500 years ago),when,throughtectonicmovement, the sea was three to five meters higher in relation to thecontemporarylandmassof Japan than at present. Analysisof the shells themselves has confirmed the changes inmarinetopography, for it is only during themaximumphasethat subtropicalspeciesof mollusc are present, indicating a higher watertemperature.

Questions:
question_stem: The word "crucial" in the passage is closest in meaning to
choices: tag: A
text: interesting

tag: B
text: important

tag: C
text: established

tag: D
text: understood
answer_key: B
explanation: crucial:至关重要的 。a 是有趣的，b 是重要的，c 是建立的，d 是理解的。综合选项，b 最符合。

question_stem: Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
choices: tag: A
text: In the last few centuries, the erosion of coastline created the Neolithic stone circle in Brittany, France, at the same time that it destroyed the medieval villages in Yorkshire, England

tag: B
text: Coastlines have changed even in recent times as shown by the current locations of certain Neolithic monuments and medieval villages

tag: C
text: Recent changes in the coastlines near the Neolithic stone circle of Er Lannic in Brittany, France, and the medieval villages in Yorkshire, England, suggest that ancient coastlines changed in similar ways

tag: D
text: Changes in coastlines can lead to the creation of islands such as Er Lannic in France or the total erosion of the cliffs as in Yorkshire in England, though no considerable changes have occurred in recent periods
answer_key: B
explanation: 提取句子主干，将括号和从句里的内容先去掉，则句子为 These have changed constantly through time,even in relatively recent periods,as can be seen from the Neolithic stone circle of Er Lannic,in Brittany,France or medieval villages in east Yorkshire,England。主语 these 指代前一句的 ancient coastlines。句子主干的大意为“海岸线始终在改变，即使在最近的时期，这一现象可以通过 Neolithic stone circle 和 medieval villages 看出“。b 选项是对原句的同义替换表达，故正确。a 选项的两个谓语动作，即 created 和 destroyed 原句中均未提及。c 选项说 recent coastline changes 和 ancient coastline changes 改变的方式一样，原句未提及。d 选项的 lead to 因果关系在原句中没有体现。

question_stem: According to paragraph 1, the city of Ephesus in western Turkey is an example of which of the following?
choices: tag: A
text: Recent changes in the shoreline that have resulted in the creation of new land

tag: B
text: Port cities that have lost shoreline due to the erosion of land

tag: C
text: The ocean's role in the formation of new land

tag: D
text: The importance of changes in shoreline to cities located inland
answer_key: A
explanation: 题干问 Ephesus in western Turkey 是以下哪项的例子。通过题干的 Ephesus in western Turkey 定位至原文最后一句话的后半部分，由 as 可以看出，答案为前半句。“silts deposited by rivers sometimes push the sea farther back,creating new land”，同义改写之后即为 a。

question_stem: Which of the following can be inferred from paragraph 2 about the effects of climate change during the Paleolithic period?
choices: tag: A
text: The amount of land not covered by water was a greater during warmer periods

tag: B
text: Warmer weather encouraged the expansion of the range of flora and fauna

tag: C
text: As a result of colder weather,land bridges became exposed

tag: D
text: The rise of sea level occurred during periods of cold weather
answer_key: C
explanation: 综合本段第3句和第4句，“When the ice sheets grew,the sea level would drop” ，当冰原增大的时候，海平面会下降；“Falls in sea level often exposed a number of important land bridges”，海平面的下降通常会暴露出大量重要的陆桥。得出推理：冰原增大是由于低温，故低温会导致陆桥显现。

question_stem: By indicating that flora and fauna of isolated or insular areas were often irreversibly affected by the changes due to the Ice Age, the author means that the flora and fauna were
choices: tag: A
text: unable to return to their previous conditions

tag: B
text: in a constant state of change

tag: C
text: completely destroyed by human colonization

tag: D
text: unevenly distributed across the area
answer_key: A
explanation: 本题可以从短语本身着手。irreversibly affected 意为“不可逆转地受到了影响“，植物和动物受到了影响即发生了改变，不可逆转即无法回到改变之前的状态，故答案为 a。

question_stem: According to paragraph 2, all of the following are true of Beringia EXCEPT
choices: tag: A
text: It may have been used by the people who first colonized North America

tag: B
text: It may have been large enough to support life

tag: C
text: It was probably still four meters under water during the glacier maximum

tag: D
text: It was probably a vast plain
answer_key: C
explanation: 根据题干的 Beringia 定位至本段倒数第二句话，故确定答案范围在最后两句话中。a 选项对应原文最后一句话，The existence of Beringia…the New World，故排除；b 选项对应倒数第二句的1,000 kilometers from the north to the south 和最后一句的 the extent to which it could have supported human life，排除；原文倒数第二句提到在 glacier maximum 的期间，海平面下降了120米，露出了一个大平原，即 Beringia,也就是说 Beringia 位于海平面之上，与 c 选项的仍旧在水面以下4米表述冲突，故 c 为正确答案；故 d 选项对应倒数第二句的 which therefore created not merely a bridge but a vast plain，排除。

question_stem: What purpose does the discussion about the Bering Strait in paragraph 2 serve in the passage?
choices: tag: A
text: It explains the idea that changes in coastlines do not necessarily result in significant alternations to existing marine life

tag: B
text: It illustrates the kind of impact that variations in land availability caused by climate change can have

tag: C
text: It provides a large amount of archaeological evidence that casts doubt on changes in sea level during the Paleolithic period

tag: D
text: It shows how ancient coastlines can serve as useful models in understanding recent changes in coastlines
answer_key: B
explanation: 通过题干的 Bering Strait 定位至本段第5句话，提到具体的白令海峡是一个例子，故往前看。前一句提到温度变低导致海平面下降，海平面下降使得陆桥出现。例子本身说的是海平面下降暴露出了白令海峡，例子和前句观点所表达的意思一样，即例子是为了说明温度变化对 land availability 的影响。答案为 B。

question_stem: The word "remnants" in the passage is closest meaning to
choices: tag: A
text: remains

tag: B
text: regions

tag: C
text: points

tag: D
text: origins
answer_key: A
explanation: remnant：剩余部分，残余。a 是遗留，b 是地区，c 是地点，d 是起源。综合选项为 a。

question_stem: According to paragraph 3, why is the height of a raised beach not a straightforward indicator of past sea level?
choices: tag: A
text: The height of the beach may have been raised or altered by human interventions in the shore environment

tag: B
text: The height of the beach may be the result of erosion over a brief period of time

tag: C
text: It is difficult to assess if the sea actually existed at that level for any significant period of time

tag: D
text: The surface of Earth may have shifted,moving the beach from its original position
answer_key: D
explanation: 通过题干定位至本段第3句，题干问原因，故答案一般位于后一句话。“In the majority of cases,the beaches lie at a higher level because the land has been raised up through isostatic uplift or tectonic movement.”，概括原因为陆地的变化导致了沙滩的的位置变化，故答案为 d。

question_stem: According to paragraph 3, which of following causes an isostatic uplift?
choices: tag: A
text: Shifts in Earth's crust

tag: B
text: A decrease in the pressure of thick ice sheets

tag: C
text: A decrease in temperature

tag: D
text: Changes in sea level
answer_key: B
explanation: 通过题干定位至本段第5句，Isostatic uplift of the land occurs when the weight of ice is removed as temperatures rise，即随着温度升高，冰块重量减轻，因此产生了 isostatic uplift，核对选项，b 为原文的同义改写，故正确。

question_stem: The word "comprising" in the passage 4 is closest in meaning to
choices: tag: A
text: taken from

tag: B
text: made up of

tag: C
text: suggesting

tag: D
text: covering
answer_key: B
explanation: comprising：组成。A 是取自，B 是组成，C 是暗示／表面，D 是覆盖。综合选项，B 为正确答案。

question_stem: Which of the following can be inferred from paragraph 4 about Tokyo Bay?
choices: tag: A
text: The coastal land currently available is smaller than it was during the Jomon period

tag: B
text: The height of raised beaches around Tokyo Bay is a poor indicator of ancient sea levels

tag: C
text: The water temperature in Tokyo Bay is lower at present than it was during the Jomon period

tag: D
text: Tectonic movement during the Jomon period was not responsible for the formation of Tokyo Bay's raised beaches
answer_key: C
explanation: 本段第二句话提到 Tokyo Bay 是 Jomon 时期的 shell mounds，最后一句话又提到分析贝类本身可以证实海洋地形的变化，因为只有在海水淹没的最高值阶段才会存在亚热带的软体动物，这暗示着更高的水温。（Analysis of the shells themselves has confirmed the changes in marine topography,for it is only during the maximum phase that subtropical species of mollusc are present,indicating a higher water temperature.）推理：软体动物的存在暗示着水温高，而 Tokyo Bay 是 Jomon 时期由软体动物组成的贝冢，故可以推出 Tokyo Bay 的水温在 Jomon 时期要比现在高。故答案为 c。