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GRE閱讀高頻機(jī)經(jīng)原文及答案:地球冷暖周期

時(shí)間: 楚薇0 分享

gre的機(jī)經(jīng)對(duì)我們的備考有很強(qiáng)的參考價(jià)值,為了方便大家,下面小編給大家?guī)?lái)GRE閱讀高頻機(jī)經(jīng)原文及答案:地球冷暖周期,來(lái)看看吧!

GRE閱讀高頻機(jī)經(jīng)原文及答案:地球冷暖周期

地球冷暖周期通過(guò)石頭含鐵量推定 新題

Recent studies of sediment in the North Atlantic’s deepwaters reveal possible cyclical patterns in the history of Earth’s climate. Therock fragments in these sediments are too large to have been transported thereby ocean currents; they must have reached their present locations by travelingin large icebergs that floated long distances from their point of origin beforemelting.

Geologist Gerard Bond noticed that some of the sedimentgrains were stained with ironoxide, evidence that they originated in localeswhere glaciers had overrun outcrops of red sandstone. Bond’s detailed analysisof deep-water sediment cores showed changes in the mix of sediment sources overtime: the proportion of these red-stained grains fluctuated back and forth fromlows of 5 percent to highs of about 17 percent, and these fluctuations occurredin a nearly regular 1,500-year cycle.

Bond hypothesized that the alternating cycles might beevidence of changes in ocean-water circulation and therefore in Earth’sclimate. He knew that the sources of the red-stained grains were generallycloser to the North Pole than were the places yielding a high proportion of“clean” grains. At certain times, apparently, more icebergs from the ArcticOcean in the far north were traveling south well into the North Atlantic beforemelting and shedding their sediment. Ocean waters are constantly moving, andwater temperature is both a cause and an effect of this movement. As watercools, it becomes denser and sinks to the ocean’s bottom. During some periods,the bottom layer of the world’s oceans comes from cold, dense water sinking inthe far North Atlantic. This causes the warm surface waters of the Gulf Streamto be pulled northward. Bond realized that during such periods, the influx ofthese warm surface waters into northern regions could cause a large proportionof the icebergs that bear red grains to melt before traveling very far into theNorth Atlantic. But sometimes the ocean’s dynamic changes, and waters from theGulf Stream do not travel northward in this way. During these periods, surfacewaters in the North Atlantic would generally be colder, permitting icebergsbearing red-stained grains to travel farther south in the North Atlantic beforemelting and depositing their sediment.

The onset of the so-called Little Ice Age (1300-1860),which followed the Medieval Warm Period of the eighth through tenth centuries,may represent the most recent time that the ocean’sdynamic changed in this way. If ongoing climate-history studies support Bond’shypothesis of 1,500-year cycles, scientists may establish a major natural rhythmin Earth’s temperatures that could then be extrapolated into the future.Because the midpoint of the Medieval Warm Period was about A.D. 850, anextension of Bond’s cycles would place the midpoint of the next warm intervalin the twenty-fourth century.

21.1. According to the passage, which of the following istrue of the rock fragments contained in the sediments studied by Bond?

A. The majority of them are composed of red sandstone.

B. They must have reached their present location over 1,500 years ago.

C. They were carried byicebergs to their present location.

D. Most of them were carried to their present location during a warm period inEarth’s climatic history.

E. They are unlikely to have been carried to their present location during theLittle Ice Age.

21.2. In the final paragraph of the passage (lines 27-33),the author is concerned primarily with

A. answering a question about Earth’s climatic history

B. pointing out a potential flaw in Bond’s hypothesis

C. suggesting a new focus for the study of ocean sediments

D. tracing the general history of Earth’s climate

E. discussing possibleimplications of Bond’s hypothesis

21.3. According to the passage, Bond hypothesized that whichof the following circumstances would allow red-stained sediment grains to reachmore southerly latitudes?

A. Warm waters being pulled northward from the GulfStream

B. Climatic conditions causing icebergs to melt relatively quickly

C. Icebergs containing a higher proportion of iron oxide than usual

D. The formation of more icebergs than usual in the far north

E. The presence of coldsurface waters in the North Atlantic

21.4. It can be inferred from the passage that in sedimentcores from the North Atlantic’s deep waters, the portions that correspond tothe Little Ice Age

A.. differ very little in composition from theportions that correspond to the Medieval Warm Period

B. fluctuate significantly in composition between the portions corresponding tothe 1300s and the portions corresponding to the 1700s

C. would be likely tocontain a proportion of red-stained grains closer to 17 percent than to 5percent

D. show a much higher proportion of red-stained grains in cores extracted fromthe far north of the North Atlantic than in cores extracted from further south

E. were formed in part as

答案:CEEC

再見(jiàn),GRE閱讀“馬后炮”之文章類型

市面上經(jīng)常有人將GRE文章分為現(xiàn)象解釋型、問(wèn)題解決型、新老觀點(diǎn)對(duì)比型等類型,并大書特書。但如果考生將過(guò)多精力花在區(qū)別文章類型上面,其實(shí)是得不償失的事情。

為什么這么說(shuō)呢?因?yàn)檫@個(gè)分類本身就有問(wèn)題。

比如一篇文章如果這么展開(kāi):

一個(gè)現(xiàn)象好奇怪呀!

傳統(tǒng)的觀點(diǎn)是:A可以解釋。

但是現(xiàn)在有新的觀點(diǎn):B可以解釋。

那這篇文章是屬于現(xiàn)象解釋型還是新老觀點(diǎn)對(duì)比型?按照以上分類,這是一篇綜合了現(xiàn)象解釋和新老觀點(diǎn)對(duì)比的文章,不能作非此即彼的論斷。

再比如,新老觀點(diǎn)對(duì)比型,這種分類暗示新老觀點(diǎn)在文章論述邏輯里的地位是對(duì)等的,例如:關(guān)于一件事情以前和現(xiàn)在的人看法不一樣。以前人們認(rèn)為_(kāi)X.但是現(xiàn)在人們認(rèn)為YYY.

那么請(qǐng)問(wèn)以下兩篇文章能否被涵蓋在內(nèi):

1. 關(guān)于一件事情以前人們的看法是_X。但是他們的看法有問(wèn)題,正確的看法應(yīng)該是YYY.

2. 關(guān)于一件事情以前人們的看法是_X。但是有一個(gè)新的看法是YYY.事實(shí)表明YYY這個(gè)看法很合理。

很明顯這兩篇文章和前面例子里的文章不一樣,它們都是有作者觀點(diǎn)態(tài)度的:1文里作者反駁前面觀點(diǎn),2文則是作者在新的看法后面引用事實(shí)表示支持。因此這兩篇文章的重心都在作者觀點(diǎn)態(tài)度上。有人可能會(huì)說(shuō),那再分細(xì)一點(diǎn),加上反駁型文章和作者評(píng)價(jià)型文章。但就算類型分得更細(xì)更嚴(yán)謹(jǐn),對(duì)我們考生來(lái)說(shuō)也沒(méi)什么實(shí)質(zhì)性的好處,相反我們還要多記一些大名詞并在做題時(shí)多花時(shí)間精力區(qū)別判斷。原因是:分類更細(xì)后,我們也只有在讀完一篇文章(而且是讀懂了)才知道這是啥類型的文章啊!這完全是馬后炮行為。

當(dāng)然這種給文章分類的初衷可能是好的,也許是為了讓我們更好地把握文章主線信息,更好地理解文章。但是最終的結(jié)果其實(shí)是有誤導(dǎo)性的,它試圖將文章固定在幾種套路里,讓我們產(chǎn)生一種套路在手,GRE閱讀我有的感覺(jué),而實(shí)際上呢它對(duì)我們?nèi)绾巫x懂一篇文章(how)沒(méi)有幫助,因?yàn)槲覀兪亲x完了讀懂了才知道這是啥類型的文章啊。而考生很多時(shí)候很難看出這種方法的問(wèn)題:厲害的考生讀懂了能辨別出文章類型,他會(huì)覺(jué)得這方法不壞,而不厲害的考生讀完了沒(méi)讀懂分辨不出來(lái),會(huì)覺(jué)得可能是自己方法掌握得不好。我覺(jué)得這可能也是某些馬后炮行為一直流傳在江湖中的原因之一。

結(jié)論是文章分類是沒(méi)什么用的馬后炮行為。關(guān)于文章“套路”“類型”,其實(shí)我們只需要知道出現(xiàn)現(xiàn)象后面極有可能解釋,解釋可能不只一個(gè),關(guān)注解釋間的關(guān)系;出現(xiàn)問(wèn)題,文章后面可能會(huì)找解決方案,方案可能不只一種,關(guān)注方案間的關(guān)系;開(kāi)始有引用觀點(diǎn),后面很有可能出現(xiàn)反駁(作者或別人);有這樣一些簡(jiǎn)單的預(yù)期就可以了。我們應(yīng)該把精力放在如何高效理解而不是找套路上面,至于如何高效理解,則不是一篇文章能說(shuō)完的,有機(jī)會(huì)再另寫文章闡述。

GRE長(zhǎng)閱讀要不要認(rèn)真讀取決于你的目標(biāo)分?jǐn)?shù)

應(yīng)對(duì)GRE閱讀考試,大家首先要關(guān)注的是節(jié)奏。 很多考生在準(zhǔn)備GREVerbal的時(shí)候,想知道長(zhǎng)閱讀是否值得認(rèn)真讀?;卮疬@個(gè)問(wèn)題前,我們可以先看下GRE Verbal的題目構(gòu)成,Verbal有兩部分,具體如下:

從上表可以看出,第二個(gè)Verbal部分沒(méi)有長(zhǎng)閱讀,所以這里和大家討論的是第一部分的長(zhǎng)閱讀。大家可以看到,短閱讀的字?jǐn)?shù)只有120字,中篇閱讀180個(gè)字,意味著60個(gè)字左右一道題。而長(zhǎng)閱讀450詞只有四題,平均100多詞解一題。這意味著長(zhǎng)閱讀是一個(gè)閱讀和得分效率相對(duì)較低的題目。

考場(chǎng)上很多考生認(rèn)真按順序一題一題進(jìn)行解答。在能力不充分時(shí),這樣做浪費(fèi)大量時(shí)間,質(zhì)量還沒(méi)有保證,得不償失。

下表給出的是幾個(gè)典型分?jǐn)?shù)對(duì)應(yīng)的錯(cuò)題數(shù)量。大家都知道GRE是一個(gè)section adapted test,半自適應(yīng)考試。Section2的難度取決于Section1的完成情況。

GRE錯(cuò)題數(shù)量及分?jǐn)?shù)對(duì)應(yīng)關(guān)系

  比如,表中第一個(gè)同學(xué),第一部分只錯(cuò)了五道題,于是他的第二個(gè)部分就進(jìn)入到了所謂的高分區(qū)間,難度系數(shù)達(dá)到了83分。他在第二部分錯(cuò)了九道題,因此他一共錯(cuò)了14道題,總分是一個(gè)非常好的分?jǐn)?shù)160分。而我們通常認(rèn)為高分檔和低分檔的準(zhǔn)入門檻的錯(cuò)題數(shù)在第一部分應(yīng)該是七道題。如果你錯(cuò)了七道題,是有可能進(jìn)到高分檔,也有可能進(jìn)到中分檔的。

  表里中間兩行的同學(xué)成績(jī),第一部分都只錯(cuò)了七道題,但他們進(jìn)入了難度不同的第二部分。第一個(gè)同學(xué)進(jìn)到了高分檔,仍然是83的難度系數(shù),他第二個(gè)部分錯(cuò)了九道題,一共錯(cuò)了16道題。我們知道一共是40道題,錯(cuò)了16道題,其實(shí)錯(cuò)誤率已經(jīng)達(dá)到了40%,用百分制來(lái)說(shuō)他應(yīng)該是只得60分,但他最后的分?jǐn)?shù)仍然是一個(gè)非常優(yōu)秀的158分,因?yàn)樗M(jìn)到的是hard模式。下一個(gè)同學(xué),第一個(gè)部分錯(cuò)了7個(gè),第二個(gè)部分進(jìn)到了中分檔,難度系數(shù)66,他第二部分做得非常好,只錯(cuò)了5道題,一共只錯(cuò)了12道題,結(jié)果他的分?jǐn)?shù)也是158分,這其實(shí)就是分?jǐn)?shù)段的價(jià)值。

  第三個(gè)同學(xué),第一個(gè)部分他錯(cuò)了9道題,第二個(gè)部分同樣進(jìn)到了中分檔,我們知道中分檔的區(qū)間第一個(gè)部分需要錯(cuò)的是7道題以上,14道題以內(nèi),他錯(cuò)了9個(gè)。第二個(gè)部分他錯(cuò)了14個(gè),一共錯(cuò)了多達(dá)23道題,但是他的最后分?jǐn)?shù)152,這是一個(gè)對(duì)于理工科同學(xué)申請(qǐng)優(yōu)秀學(xué)校仍然夠用的語(yǔ)文分?jǐn)?shù)。

  根據(jù)分?jǐn)?shù)分布發(fā)現(xiàn),最后兩個(gè)同學(xué)一個(gè)人錯(cuò)了12個(gè),另一個(gè)人錯(cuò)了23個(gè),這個(gè)人比前一個(gè)人多錯(cuò)了11道題,結(jié)果他們的分?jǐn)?shù)差卻只有差了6分,說(shuō)明進(jìn)到中分檔以后的錯(cuò)題分?jǐn)?shù)就不是特別敏感了。

  但高分檔中的同學(xué),section2錯(cuò)了16個(gè),比進(jìn)入中分檔同學(xué)錯(cuò)的還多,但分?jǐn)?shù)卻一樣,說(shuō)明只要進(jìn)入到了高分檔,第二個(gè)部分其實(shí)想要沖擊160之內(nèi)分?jǐn)?shù)是相當(dāng)容易的。

  基于上述分析,針對(duì)到底要不要做長(zhǎng)閱讀我給大家的建議是,取決于你的GRE目標(biāo)分?jǐn)?shù)。如果你的目標(biāo)分?jǐn)?shù)是160分以上,則你必須認(rèn)真完成長(zhǎng)閱讀。但如果你的目標(biāo)分?jǐn)?shù)是一個(gè)比較穩(wěn)妥的150到160,我認(rèn)為你是可以戰(zhàn)略性擱置長(zhǎng)閱讀的。這個(gè)分?jǐn)?shù)段的同學(xué)應(yīng)該把更多時(shí)間花在擅長(zhǎng)的題目上,而不是非要保證把所有題目做完。相比有同學(xué)在有限時(shí)間內(nèi)穩(wěn)妥做完題目,強(qiáng)求做完所有題目就無(wú)法不能保證準(zhǔn)確率。

  GRE閱讀詞匯精選之貶低蔑視

  abase v.貶抑,使卑下

  belittle v.輕視,貶抑

  condescension n.自以為高人一等,貶低(別人)

  debase v.貶低,貶損

  decry v.責(zé)難,貶低(價(jià)值)

  demean v.貶抑,降低

  depreciate v.貶低,貶值

  derogate v.貶低,誹謗

  detractor v.貶低者

  disparage v.貶抑,· 輕蔑

  epithet n.(貶低人的)短語(yǔ)或形容詞

  pejorative adj.帶有輕蔑意義的,· 貶低的

  downplay v.貶低,· 低估

  underrate v.低估,估計(jì)過(guò)低,看輕

  contempt n.輕視,· 鄙視

  contemptible adj.令人輕視的

  disdain v.輕視、鄙視

  disdainful adj.鄙視的

  scorn n.v.輕蔑、瞧不· 起

  misprision n.輕視,· 蔑視

  despise vt.輕視

  slight v.\n. 輕蔑,怠慢 a.輕微的,纖細(xì)的

  flout v.蔑視,· 違抗

  defiance n.蔑視,挑釁

  sneer v.嘲笑,· 鄙視

  degrade v.降格,· 降級(jí)

  demote v.降級(jí),· 降職

  relegate v.降級(jí),· 貶謫

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