新东方潘泓甫：ACT最新真题72E阅读自然科学篇解读-新东方前途出国

  1、先从官方指南如何选文章出题开始说起。

　　官方指南第三章中提到“Thepassages in the Reading Test come from published materials, such as books andmagazines, that are like those a first-year college student can expect to readfor a class.”

　　可见ACT阅读检测的是学生是否有完成美国本科一年级读书的能力，而本科学习最大的特点是海量阅读。根据我自己在美国读书的经验，平均每天要阅读30-70页正常字体大小的A4纸。做一个简单计算，一页A4纸大概有1000英文单词，取阅读量的中值50页，也就是一天要有50000字的阅读量。如果预期每天用4个小时完成作业，换算下来就是每秒钟3-4个单词。

　　所以考生普遍觉得ACT阅读的时间太紧了，要求的速度太快，但是我们通过上面的计算也发现了其中的道理。如果某位同学达不到ACT阅读速度的要求，往往意味着在美国读书要比他人花更多的时间完成相同质量的作业，如果其他人平均每天有6-7小时睡眠，那就意味着这位同学每天能有的睡眠时间更短，如果阅读速度太慢，熬夜就会变成逼不得已的选择。

　　2、那ACT阅读具有时间紧任务多的特点该怎么破呢？

　　官方指南第二章中同时给出了解决方式 “the best way to get ready for a game or performance is to prepareactively”，在主动准备方面中国学生最欠缺的往往是主动阅读的能力。

　　针对出题准则国学生的特点，总结出三个读文章的阶段：

　　初期备考考生要先能做到在一句话中识别出关键词来把握文章走向；

　　中期备考要关注文章的结构和主旨；

　　后期备考在前面的基础上要关注的是前后文的预测能力。

　　这三个阶段是逐步从被动阅读走向主动阅读的路径。

　　3、紧接着，用一篇近期真题来展示中期备考的阅读方法：结构化阅读背景扩展

　　pika是一种耳朵短而圆、没有尾巴的动物。据说鼠兔是因为外形酷似仓鼠而得名。鼠兔没有犬齿，门齿可不断生长。前肢五指，后肢四趾。爪子细而弯，适合掘土。毛色因种而异，由灰色、灰褐色至锈褐色，夏毛要比冬毛淡。(选自Wikipedia)

　　文章赏析：

　　NATURAL SCIENCE: This passage is adapted fromthe article

　　"Silence of the Pikas" by Wendee Holtcamp (C2010 by WendeeHoltcamp).Introduction:

　　silence of pikas

　　根据提炼的结构概括：pika的沉默

　　Pikas, a diminutive alpine-dwelling rabbitrelative,

　　are unique among alpine mammals in that theygather

　　up vegetation throughout summer-includingflowers,

　　grasses，leaves, evergreen needles, and even pine

　　cones- and live off the hay pile throughoutwinter,

　　rather than hibernating or moving downslope.But

　　increasingly warm temperatures may drive themto the

　　brink: the high-energy mammals can overheat anddie

　　at temperatures as mild as 25 degrees Celsiusif they

　　can't regulate their body temperature by movinginto

　　the cooler microclimate under the talus. Andsince they

　　already live near the tops of mountains, when aparticu-

　　lar talus field’s microclimate becomesinhospitable，

　　they simply have nowhere to go.

　　1st:

　　pika unique, gather up summer, live off haypile winter;

　　warm drive pika brink, overheat and die;

　　∵top mountains, no where to go

　　根据提炼的结构概括：pika是独特的，夏天收集食物冬天以其为生。变暖会危及pika生存，过热死去。考虑到他们已经生活在山顶，变暖将无处可逃。

　　Sometimes called cony, mouse hare rock rabbit,

　　or whistling hare, the pika has a narrow niche.They

　　live only in talus fields, and these must lieadjacent to

　　alpine meadows or other vegetation so they haveaccess

　　to plants for food and bay farming. The talusrock fields

　　must have boulders of a certain size; scree, asimilar

　　habitat with smaller rocks, won't do. Rocksprovide

　　safe haven from pikas’ main predator, weasels.But per-

　　haps more important, the interstices betweenthe rocks

　　provide both a cool, moist microclimate wherepikas

　　cool down during hot summer days and also theperfect

　　sanctuary in which to settle during the longwinter's

　　night. They don’t huddle together like manyother

　　mammals, as far as scientists can tell, butremain

　　fiercely territorial and solitary throughoutthe winter,

　　guarding their hay piles with their lives. As asnowpack

　　settles over the land, it insulates the Earthand main-

　　tains a certain underground temperature atwhich pikas

　　can survive, just below freezing. With warmingtemper-

　　atures reducing snowpack in many mountainousareas,

　　in a strange twist of fate, global warming cancause

　　pikas to freeze.

　　2nd:

　　pika narrow niche, only talus field, alpinemeadows, boulders, not scree;

　　rock safe + cool summer, perfect sanctuarywinter;

　　not huddle, solitary;

　　snowpack maintain underground temperature notfreeze, pika survive;

　　warm strange, cause freeze

　　根据提炼的结构概括：pika的生境很有限，只在紧邻alpinemeadows的talusfield，而且必须是大块石头来为他们提供安全保障的位置，scree则不行，同时夏天提供阴凉冬天提供庇护。pika喜欢独居，高山冰雪能保证气温在零度以上保证他们生存。而全球变暖会因为减少了高山冰雪儿使得pika被冻死。

　　Biologists have dubbed mountaintop habitat

　　patches “sky islands” because the valleys inbetween

　　are as uninhabitable as the sea for nonmobilealpine

　　species. This creates an ideal scenario to testthe pre-

　　dictions of one of ecology's key theories:island bio-

　　geography. Individual pikas have a relativelylimited

　　distance they can disperse, around twokilometers, so

　　they can’t just shift from one mountain toanother. At

　　the population level, they’re stuck on aparticular

　　mountain range. In the 1990s, biologist ErikBeever and

　　colleagues surveyed pikas throughout thehydrographic

　　Great Basin-a heart-shaped 500,000 squarekilometer

　　intermontane plateau dotted with 314 mountainranges,

　　incorporating parts of California, Nevada,Utah,

　　Oregon, Idaho and Arizona—and were unable tofind

　　pikas in 6 of 25 mountain ranges that they hadoccupied

　　in the late 20th century. Was the cause of pikaextirpa-

　　tions (disappearances) climatic, anthropogenic,or

　　biogeographical?

　　3rd:

　　“sky islands” because uninhabitable;

　　ideal to test island biogeography(IB);

　　pikas limited distance, stuck on mountain;

　　EB survey, unable find pikas 6/25 mountainrange;

　　what cause?

　　根据提炼的结构概括：科学家称其为“sky island”因为适宜生存，是很理想检验island biogeography理论的方式。pika生活范围有限，在高山上。根据EB调查，25座山的其中6座已经没有pika了，到底是什么造成的呢？

　　Island biogeography theory says that “speciesare

　　predicted to remain on large islands andislands that are

　　not very isolated from mainland [habitat],”explains

　　Beever, who did much of his work while agraduate

　　student under Mary Peacock, at the Universityof

　　Nevada-Reno. He and colleagues found pikapopula-

　　tions persisted in mountain ranges with moretalus

　　habitat available--supporting one prediction ofisland

　　biogeography theory--but pikas were not morelikely

　　to persist at sites closer to the RockyMountain or

　　Sierra Nevada “mainland” ranges.

　　4th:

　　IB, species remain large islands, not isolated,by EB and MP;

　　pika support large, not closer

　　根据提炼的结构概括：islandbiogeography认为物种倾向于较大岛屿以及不孤立的岛屿。pika证实了倾向较大地域的特征，但是没有支持不孤立的特征。

　　“Here isolation doesn’t have anything to dowith

　　whether they're lost or not,” Beever says. Notonly that,

　　“the sheer size of a mountain range in thiscase isn’t

　　very predictive of patterns of loss. [And] ifwe count

　　the amount of habitat, that’s less important thanthese

　　climatic influences.” Ultimately, the factorsmost

　　strongly associated with pika disappearancewere cli-

　　matic; specifically, warmer and drier sites,which

　　tended to be lower down the mountains. Inanother

　　study published in Ecological Applications,Beever,

　　University of Colorado researcher Chris Ray,and other

　　colleagues revealed that acute cold stress andchronic

　　heat stress (in other words, cold snaps andoverall

　　hotter summers) affect pika more thanindividual very

　　hot days.

　　5th:

　　habit < climatic influence, EB;

　　pika disappearance, warmer and drier sites;

　　another study, acute cold stress and chronicheat stress > individual hot days

　　根据提炼的结构概括：EB认为生境的影响远不及气候，具体来说是更加温暖和干燥的气候导致了pika消失。另一项研究表明，迅速变冷和持续炎热要比短暂热几天更加有破坏力。

　　“The problem with global warming is that if

　　[pikas] lose [their] snowpack, which providesinsula-

　　tion in winter, they freeze to death, and ifthe ambient

　　air temperature beats up too much in summerthen they

　　[overheat]. That’s the challenge,” Peacocksays, who

　　has studied pika population genetics. “They're already

　　at the top of the mountain. If you heat it npsubstan-

　　tially, there’s no place for them to go.”

　　6th:

　　lose snowpack, freeze to death; overheatchallenge, MP;

　　top, nowhere to go

　　根据提炼的结构概括：失去积雪会冻死，过热也会死，已经在山顶，无处可躲。

　　结构化的分析可以帮助考生找到文章的脉络，知道如何在实际考试中变速阅读，提取关键信息。

　　习题解析：

　　挑选有代表性的习题，分析如下。

　　31. The primary purpose of the passage is todiscuss the:

　　A.  methodsscientists use to track the numbers of

　　pikas in several regions.

　　B.  rolepika social behavior plays in their ability to

　　adapt to changing conditions.

　　C.  causesof pika disappearances and scientists' pro-

　　posed solutions to the disappearances.

　　D.   habitatand conditions in which pikas flourish and

　　the causes of their disappearances.

　　答案D：题干 “primarypurpose”判断是主旨类型。A强调的是追踪pika的方法，不是方法；B强调pika适应环境，不是适应；C强调pika消失原因和对策，没提对策；D强调pikaflourish habitat和消失原因，正确。

　　35. It can most reasonably be inferred from thepassage

　　that one reason pikas easily overheat is that they:

　　A.  becomeoverwhelmed by a thick snowpack.

　　B.  are ahigh-energy mammal.

　　C.  huddletogether in interstices.

　　D.  insulate themselves inside hay piles.

　　答案B：题干 “inferredfrom”判断需要推测，“overheat”定位L6-10。

　　But increasingly warm temperatures may drivethem to the brink: the high-energy mammals can overheatand die at temperatures as mild as 25 degrees Celsius if they can't regulatetheir body temperature by moving into the cooler microclimate under the talus.

　　36. The passage indicates that compared to atalus field,

　　scree habitats have:

　　F.    morefood.

　　G.   fewerpredators.

　　H.   smallerrocks.

　　J． better access to interstices.

　　答案H：题干 “comparedto”判断为对比类型，“screehabitats”定位L19-21。

　　The talus rock fields must have boulders of acertain size; scree, a similar habitat with smaller rocks, won't do.

　　37. The passage indicates that the perfectsanctuary for a

　　pika on a long winter night is located:

　　A.  on ahay pile near an alpine talus field.

　　B.  in analpine meadow near a talus field.

　　C.    onthe top of a mountain adjacent to a talus field.

　　D.   inthe interstices between rocks in an alpine talus

　　field.

　　答案D：题干有“perfectsanctuary”出现，原文定位L24-27。

　　But perhaps more important, the interstices between the rocks provide both acool, moist microclimate where pikas cool down during hot summer days and alsothe perfect sanctuary in which to settle duringthe long winter's night.

　　38. In the passage, the behavior of pikasduring winter is

　　characterized in part as:

　　F.    fiercelyterritorial.

　　G.   relativelyrelaxed.

　　H.   predatory.

　　J.  social.

　　答案F：题干“behaviorof pikas characterized as”判断为概括类型，“during winter”定位L27-30。

　　They don’t huddle together like many other mammals,as far as scientists can tell, but remain fiercelyterritorial and solitary throughout the winter,guarding their hay piles with their lives.

　　4、结构化阅读总结。

　　ACT每篇阅读的文字量大概是1000字，4篇文章共4000字；每道题目大概是80个字，40道题共3200字。35分钟要完成大约7200字的阅读量，即每秒种要读3-4个字，对比篇首在美国学习的日常阅读量，二者几乎是一致的。

　　在这种考试设计下是无法逐字逐句清晰的分析判断思考文章所有信息的，想要完成这个任务，就需要结构化的阅读。也就是说，在读文章的时候不断分析的是文章的结构和主旨是什么，相关度越高的内容则越仔细看，反之。例如，OG第二套题阅读第二篇文章，introduction部分明确写了是关于thecharacter of Tomas Jefferson的，所以当第一段看到大段引用林肯的话的时候就应该扫读，只要掌握林肯对于Jefferson的观点主旨即可，这样可以节省大量时间。

　　ACT阅读备考是一个很考验思考能力的过程，考生要不断反思，发现阅读问题，再用合适的方法去训练，才能取得理想的成绩。