Part Five
That experiences influence subsequent behavior is evidence of an obvious but nevertheless remarkable activity called remembering. Learning could not occur without the function popularly named memory. Constant practice has such as effect on memory as to lead to skillful performance on the piano, to recitation of a poem, and even to reading and understanding these words. So-called intelligent behavior demands memory , remembering being a primary requirement for reasoning. The ability to solve any problem or even to recognize that a problem exists depends on memory. Typically, the decision to cross a street is based on remembering many earlier experiences .
Practice （or review）tends to build and maintain memory for a task or for any learned material. Over a period of no practice what has been learned tends to be forgotten; and the adaptive consequences may not seem obvious. Yet, dramatic instances of sudden forgetting can seem to be adaptive. In this sense, the ability to forget can be interpreted to have survived through a process of natural selection in animals. Indeed, when one's memory of an emotionally painful experience lead to serious anxiety, forgetting may produce relief. Nevertheless, an evolutionary interpretation might make it difficult to understand how the commonly gradual process of forgetting survived natural selection.
In thinking about the evolution of memory together with all its possible aspects, it is helpful to consider what would happen if memories failed to fade. Forgetting clearly aids orientation in time, since old memories weaken and the new tend to stand out, providing clues for inferring duration. Without forgetting, adaptive ability would suffer, for example ,learned behavior that might have been correct a decade ago may no longer be. Cases are recorded of people who （by ordinary standards）forgot so little that their everyday activities were full of confusion. This forgetting seems to serve that survival of the individual and the species.
Another line of thought assumes a memory storage system of limited capacity that provides adaptive flexibility specifically through forgetting. In this view, continual adjustments are made between learning or memory storage （ input）and forgetting （output）. Indeed, there is evidence that the rate at which individuals forget is directly related to how much they have learned. Such data offers gross support of contemporary models of memory that assume an input-output balance.
17. From the evolutionary point of view,__.
（A）forgetting for lack of practice tends to be obviously inadaptive .
（B）if a person gets very forgetful all of a sudden he must be very adaptive
（C）the gradual process of forgetting is an indication of an individual' s adaptability
（D）sudden forgetting may bring about adaptive consequences
18. According to the passage, if a person never forgot ,__.
（A）he would survive best
（B）he would have a lot of trouble
（C）his ability to learn would be enhanced
（D）the evolution of memory would stop
19. From the last paragraph we know that__.
（A）forgetfulness is a response to learning
（B）the memory storage system is an exactly balanced input-output system
（C）memory is a compensation for forgetting
（D）the capacity of a memory storage system is limited because forgetting occurs
20. In this article, the author tries to interpret the function of__.
（A）remembering （B）forgetting（C）adapting D）experiencing
Unit 2（1995）Part5
重點(diǎn)詞匯：
subsequent（隨后的）←sub+sequ+ent，sub-在下，sequ（=follow）詞根“跟隨”，-ent形容詞后綴。Be sure not to tell a first falsehood, and you needn't fear being detected in any subsequent ones.千萬別說第一個(gè)謊話，這樣就不用害怕在隨后的謊話中被人發(fā)現(xiàn)。
duration（持久；持續(xù)時(shí)間）即dur+ation，dur詞根“持續(xù)”，-ation名詞后綴。同根詞：durable（持久的）←dur+able可……的；endurance（持久力；忍耐力）←en使……+dur+ance。It is not the strength but the duration of great sentiment that makes great men.造就偉人的不是力量，而是偉大情操的持久。
contemporary（當(dāng)代的；同時(shí)代的；同時(shí)代的人）←con+tempor+ary，con-一起，tempor看作temper（性情），-ary后綴，“性情相同的（人）就是同時(shí)代的（人）”。Most contemporary books give the impression of having been manufactured in a day, out of books read the day before.大部分當(dāng)代書籍給人的印象，是花一天工夫用前一天讀過的書加工而成的。
難句解析：
①That experiences influence subsequent behaviour is evidence of an obvious but nevertheless remarkable activity called remembering.
本句的主語(yǔ)是個(gè)從句That experiences influence subsequent behaviour，而后面是一個(gè)簡(jiǎn)單的系表結(jié)構(gòu)is evidence，只不過evidence后面的修飾成分較多，里面的兩個(gè)形容詞obvious和remarkable之間還用了but nevertheless來表達(dá)一種轉(zhuǎn)折關(guān)系。
注意在閱讀的時(shí)候先要抓住主干結(jié)構(gòu)，特別是主語(yǔ)從句。在表語(yǔ)的部分要能夠一眼認(rèn)出其核心結(jié)構(gòu)是evidence of activity。
② Constant practice has such as effect on memory as to lead to skilful performance on the piano, to recitation of a poem, and even to reading and understanding these words.
本句的主干很簡(jiǎn)單，就是Constant practice has... effect on memory，主要的結(jié)構(gòu)是such as... as...，在后一個(gè)as的后面有一個(gè)不定式，而這個(gè)不定式有三個(gè)并列的賓語(yǔ)to skilful performance on the piano, to recitation of a poem, and even to reading and understanding these words，注意這里的三個(gè)to都是介詞，和動(dòng)詞lead構(gòu)成詞組。
注意先抓主干結(jié)構(gòu)，另外要注意such as... as...是一種舉例子的形式。
③ Over a period of no practice what has been learned tends to be forgotten; and the adaptive consequences may not seem obvious.
本句可一分為二，在分號(hào)處分開，前面的分句中over a period of no practice是個(gè)時(shí)間狀語(yǔ)，主語(yǔ)是個(gè)從句what has been learned，謂語(yǔ)是tends to be forgotten，后面的結(jié)構(gòu)非常簡(jiǎn)單。
理解本句以及下面幾句的功夫不在文字上，而是要求同學(xué)們對(duì)于進(jìn)化論的假設(shè)和其與記憶的關(guān)系有一個(gè)明確的認(rèn)識(shí)。在這里我們要知道，作者認(rèn)為遺忘是一種生物在進(jìn)化中適應(yīng)外界殘酷現(xiàn)實(shí)的適應(yīng)性行為，因?yàn)橹挥型袅诉^去的不愉快經(jīng)歷，一個(gè)生命才有可能活得更加生機(jī)勃勃。而這樣的觀點(diǎn)的一種必然推論就是迅速遺忘要優(yōu)于慢速遺忘，因?yàn)橥迷娇炀驮侥苓m應(yīng)外部世界。那么在這里作者就指出用進(jìn)化論適應(yīng)性的觀點(diǎn)來解釋遺忘有局限性。
④ Nevertheless, an evolutionary interpretation might make it difficult to understand how the commonly gradual process of forgetting survived natural selection.
本句的主語(yǔ)是an evolutionary interpretation，謂語(yǔ)might make，而賓語(yǔ)的部分比較復(fù)雜，有一個(gè)形式賓語(yǔ)it，在真正的作賓語(yǔ)的不定式中還有一個(gè)從句how the commonly gradual process of forgetting survived natural selection。
⑤ In thinking about the evolution of memory together with all its possible aspects, it is helpful to consider what would happen if memories failed to fade.
本句的主干是it is helpful to do sth.，真正的主語(yǔ)是to consider這個(gè)不定式，當(dāng)然它里面還包含了一個(gè)帶條件從句的賓語(yǔ)從句。逗號(hào)前面的是一個(gè)狀語(yǔ)。
注意在閱讀的時(shí)候先要抓住主干結(jié)構(gòu)，同時(shí)看清主句中的it是一個(gè)形式主語(yǔ)，指代的是后面的不定式結(jié)構(gòu)。而前面的一個(gè)its應(yīng)該是指memory。
⑥ Another line of thought assumes a memory storage system of limited capacity that provides adaptive flexibility specifically through forgetting.
本句的主干是Another line of thought assumes a memory storage system，在這里assume是一個(gè)及物動(dòng)詞。賓語(yǔ)a memory storage system后面有一個(gè)of引導(dǎo)的介詞詞組和定語(yǔ)從句來修飾它。
注意一些詞的意思，capacity在這里應(yīng)被理解為“容量”，而非“能力”；flexibility是“靈活性”而非“彈性”。
試題解析：
17．【正確答案】 [D]
意為：突然失去記憶力會(huì)導(dǎo)致生存適應(yīng)問題。文章第一段指出，人生許多問題的解決依賴于我們對(duì)過去經(jīng)歷過的事情的記憶。第二段第二、三句指出，如果我們不及時(shí)復(fù)習(xí)或練習(xí)已學(xué)過的東西的話，過一段時(shí)間，我們可能忘記它，這種情況所造成的適應(yīng)性（adaptive）后果也許不太明顯。然而，突然失去記憶力卻會(huì)對(duì)適應(yīng)帶來明顯后果。舉個(gè)例子來說，假如你一覺醒來，發(fā)覺自己失去了一切記億，那樣會(huì)發(fā)生什么呢？
A意為：由于缺乏練習(xí)所造成的遺忘很明顯不利于生存適應(yīng)。這與第二段第二句的意思相反。B意為：如果一個(gè)人突然（all of a sudden）變得健忘，他肯定是非常適應(yīng)生活的。這與第二段第三句表達(dá)的內(nèi)容相反。C意為：逐漸的遺忘過程證明了人的（較強(qiáng)的）適應(yīng)能力。第二段第四句指出，遺忘可以被看作動(dòng)物中自然選擇（natural selection）過程中遺留給人的一種能力。第三段最后一句指出，遺忘（指逐漸的遺忘）似乎對(duì)每個(gè)個(gè)體或整個(gè)物種來說有其生存價(jià)值?？梢?，逐漸的遺忘過程是人在物種間的生存競(jìng)爭(zhēng)過程中形成的，它是人們適應(yīng)外部世界的結(jié)果。C則將人的適應(yīng)能力看作是逐漸遺忘過程的結(jié)果，這顯然顛倒了邏輯關(guān)系。
18．【正確答案】[B]
第三段第三、四句指出，沒有遺忘過程，人就無法適應(yīng)。例如，十年前正確的做法現(xiàn)在未必合適，所以應(yīng)忘記它。對(duì)遺忘很少的人的調(diào)查也表明：他們的日?；顒?dòng)缺乏頭緒。
A意為：他適于生存。這與事實(shí)相反。C意為：他學(xué)習(xí)的能力會(huì)得到加強(qiáng)。這也與事實(shí)相反，事實(shí)是：所學(xué)的東西在大腦中會(huì)無頭緒可尋。D意為：記憶力的進(jìn)化就會(huì)停止。
19．【正確答案】 [A]
意為：遺忘是對(duì)學(xué)習(xí)的一種反應(yīng)。文章最后一段指出，對(duì)記憶力也可以做另一種解釋：記憶的儲(chǔ)存系統(tǒng)總儲(chǔ)量有限，遺忘使這一系統(tǒng)具有了靈活性。這種看法認(rèn)為：在學(xué)習(xí)或存儲(chǔ)（輸入）與遺忘（輸出）之間有一個(gè)不斷調(diào)整過程。事實(shí)上，有證據(jù)表明：遺忘率與學(xué)習(xí)的東西的量直接相關(guān)，這對(duì)現(xiàn)代記憶模式——輸入——輸出保持平衡——提供了證據(jù)。
B意為：記憶儲(chǔ)存系統(tǒng)是一個(gè)輸入輸出完全平衡的系統(tǒng)。根據(jù)原文，確有一種理論認(rèn)為或推測(cè)（assume）記憶儲(chǔ)存系統(tǒng)是一個(gè)輸入輸出平衡的系統(tǒng)，但也僅是假設(shè)而已，另外，exactly一字用得欠妥，太絕對(duì)化。C意為：記憶力是對(duì)遺忘的一個(gè)補(bǔ)償。嚴(yán)格地來講，forgetting與remembering都是memory的一個(gè)組成部分，是一個(gè)部分與整體間的關(guān)系，不能對(duì)照而言D意為：記憶的儲(chǔ)存系統(tǒng)總儲(chǔ)量有限，這是由遺忘造成的。原文只是說遺忘使記憶儲(chǔ)存系統(tǒng)更具適應(yīng)力，不是說它造成了記億儲(chǔ)存系統(tǒng)的有限性。
20．【正確答案】 [B]
本文主要談的是遺忘過程的作用（function），它是人生存適應(yīng)機(jī)制的一個(gè)很重要的過程，這是文章的第二、三、四段所旨在說明的，對(duì)照而言，第一段所談的內(nèi)容（remembering）只不過是這個(gè)討論的引子。
A意為：記憶，記住。C意為：適應(yīng)。D意為：體驗(yàn)。
全文翻譯：
過去的經(jīng)歷會(huì)影響日后的行為，這就表明存在著一種明顯但卻非凡的腦力活動(dòng)——記憶。如果沒有大家稱之為記憶的功能，學(xué)習(xí)便不能發(fā)生。反復(fù)練習(xí)對(duì)記憶有很大影響，可以使人們熟練地演奏鋼琴、背誦詩(shī)歌、乃至總結(jié)和理解這些詞句。用于解決問題或是辨別出有問題存在的所謂的智力行為需要記憶，記憶能力是推理的一個(gè)基本需求。解決任何問題，甚至是識(shí)別問題存在的能力都取決于記憶。最典型的是，決定過街也要憑借許多對(duì)以前經(jīng)歷的記憶。
實(shí)踐（或稱復(fù)習(xí)）就是建立并保持對(duì)某一任務(wù)或所學(xué)材料的記憶。有一段時(shí)間不實(shí)踐，學(xué)到的東西往往就會(huì)忘記（漸進(jìn)性地遺忘）；其適應(yīng)性結(jié)果也就顯得不太明顯。然而戲劇性地突然遺忘的例子也可被看做具有適應(yīng)性。從這個(gè)意義上說，遺忘能力可解釋為動(dòng)物在自然選擇的過程中幸存下來的能力。的確，如果記住一段痛苦的情感經(jīng)歷會(huì)導(dǎo)致嚴(yán)重的焦慮，那么遺忘倒可以使人得到解脫。然而，進(jìn)化論的解釋可能會(huì)使人難以理解普遍的漸進(jìn)遺忘過程是如何在自然選擇中幸存下來的。
在考慮記憶的進(jìn)化及其所有可能的方面時(shí)，思考一下如果記憶不會(huì)消失會(huì)產(chǎn)生什么結(jié)果是很有用處的。顯然，遺忘有助于時(shí)間的定位，因?yàn)榕f的記憶淡忘，新的記憶往往就突出，從而為推算持續(xù)的時(shí)間提供線索。沒有遺忘，適應(yīng)會(huì)受影響，例如，已學(xué)會(huì)的行為十
年前可能是正確的，現(xiàn)在則不然了。有記錄表明，有些人（按一般標(biāo)準(zhǔn)）忘的太少，以致日常生活常混亂不堪。因此遺忘似乎有助于個(gè)體及物種的存活。
另一種思路則假定人的記憶存儲(chǔ)系統(tǒng)儲(chǔ)量有限，這個(gè)系統(tǒng)專門通過遺忘提供適應(yīng)的靈活性。根據(jù)這個(gè)觀點(diǎn)，在學(xué)習(xí)或記憶儲(chǔ)存（輸入）和遺忘（輸出）之間要不斷進(jìn)行調(diào)整。的確，表明個(gè)人的遺忘速度與學(xué)習(xí)東西的多少有直接的關(guān)系。這些數(shù)據(jù)為假定輸入——輸出持衡的當(dāng)代記憶模式提供了明確的證據(jù)。
That experiences influence subsequent behavior is evidence of an obvious but nevertheless remarkable activity called remembering. Learning could not occur without the function popularly named memory. Constant practice has such as effect on memory as to lead to skillful performance on the piano, to recitation of a poem, and even to reading and understanding these words. So-called intelligent behavior demands memory , remembering being a primary requirement for reasoning. The ability to solve any problem or even to recognize that a problem exists depends on memory. Typically, the decision to cross a street is based on remembering many earlier experiences .
Practice （or review）tends to build and maintain memory for a task or for any learned material. Over a period of no practice what has been learned tends to be forgotten; and the adaptive consequences may not seem obvious. Yet, dramatic instances of sudden forgetting can seem to be adaptive. In this sense, the ability to forget can be interpreted to have survived through a process of natural selection in animals. Indeed, when one's memory of an emotionally painful experience lead to serious anxiety, forgetting may produce relief. Nevertheless, an evolutionary interpretation might make it difficult to understand how the commonly gradual process of forgetting survived natural selection.
In thinking about the evolution of memory together with all its possible aspects, it is helpful to consider what would happen if memories failed to fade. Forgetting clearly aids orientation in time, since old memories weaken and the new tend to stand out, providing clues for inferring duration. Without forgetting, adaptive ability would suffer, for example ,learned behavior that might have been correct a decade ago may no longer be. Cases are recorded of people who （by ordinary standards）forgot so little that their everyday activities were full of confusion. This forgetting seems to serve that survival of the individual and the species.
Another line of thought assumes a memory storage system of limited capacity that provides adaptive flexibility specifically through forgetting. In this view, continual adjustments are made between learning or memory storage （ input）and forgetting （output）. Indeed, there is evidence that the rate at which individuals forget is directly related to how much they have learned. Such data offers gross support of contemporary models of memory that assume an input-output balance.
17. From the evolutionary point of view,__.
（A）forgetting for lack of practice tends to be obviously inadaptive .
（B）if a person gets very forgetful all of a sudden he must be very adaptive
（C）the gradual process of forgetting is an indication of an individual' s adaptability
（D）sudden forgetting may bring about adaptive consequences
18. According to the passage, if a person never forgot ,__.
（A）he would survive best
（B）he would have a lot of trouble
（C）his ability to learn would be enhanced
（D）the evolution of memory would stop
19. From the last paragraph we know that__.
（A）forgetfulness is a response to learning
（B）the memory storage system is an exactly balanced input-output system
（C）memory is a compensation for forgetting
（D）the capacity of a memory storage system is limited because forgetting occurs
20. In this article, the author tries to interpret the function of__.
（A）remembering （B）forgetting（C）adapting D）experiencing
Unit 2（1995）Part5
重點(diǎn)詞匯：
subsequent（隨后的）←sub+sequ+ent，sub-在下，sequ（=follow）詞根“跟隨”，-ent形容詞后綴。Be sure not to tell a first falsehood, and you needn't fear being detected in any subsequent ones.千萬別說第一個(gè)謊話，這樣就不用害怕在隨后的謊話中被人發(fā)現(xiàn)。
duration（持久；持續(xù)時(shí)間）即dur+ation，dur詞根“持續(xù)”，-ation名詞后綴。同根詞：durable（持久的）←dur+able可……的；endurance（持久力；忍耐力）←en使……+dur+ance。It is not the strength but the duration of great sentiment that makes great men.造就偉人的不是力量，而是偉大情操的持久。
contemporary（當(dāng)代的；同時(shí)代的；同時(shí)代的人）←con+tempor+ary，con-一起，tempor看作temper（性情），-ary后綴，“性情相同的（人）就是同時(shí)代的（人）”。Most contemporary books give the impression of having been manufactured in a day, out of books read the day before.大部分當(dāng)代書籍給人的印象，是花一天工夫用前一天讀過的書加工而成的。
難句解析：
①That experiences influence subsequent behaviour is evidence of an obvious but nevertheless remarkable activity called remembering.
本句的主語(yǔ)是個(gè)從句That experiences influence subsequent behaviour，而后面是一個(gè)簡(jiǎn)單的系表結(jié)構(gòu)is evidence，只不過evidence后面的修飾成分較多，里面的兩個(gè)形容詞obvious和remarkable之間還用了but nevertheless來表達(dá)一種轉(zhuǎn)折關(guān)系。
注意在閱讀的時(shí)候先要抓住主干結(jié)構(gòu)，特別是主語(yǔ)從句。在表語(yǔ)的部分要能夠一眼認(rèn)出其核心結(jié)構(gòu)是evidence of activity。
② Constant practice has such as effect on memory as to lead to skilful performance on the piano, to recitation of a poem, and even to reading and understanding these words.
本句的主干很簡(jiǎn)單，就是Constant practice has... effect on memory，主要的結(jié)構(gòu)是such as... as...，在后一個(gè)as的后面有一個(gè)不定式，而這個(gè)不定式有三個(gè)并列的賓語(yǔ)to skilful performance on the piano, to recitation of a poem, and even to reading and understanding these words，注意這里的三個(gè)to都是介詞，和動(dòng)詞lead構(gòu)成詞組。
注意先抓主干結(jié)構(gòu)，另外要注意such as... as...是一種舉例子的形式。
③ Over a period of no practice what has been learned tends to be forgotten; and the adaptive consequences may not seem obvious.
本句可一分為二，在分號(hào)處分開，前面的分句中over a period of no practice是個(gè)時(shí)間狀語(yǔ)，主語(yǔ)是個(gè)從句what has been learned，謂語(yǔ)是tends to be forgotten，后面的結(jié)構(gòu)非常簡(jiǎn)單。
理解本句以及下面幾句的功夫不在文字上，而是要求同學(xué)們對(duì)于進(jìn)化論的假設(shè)和其與記憶的關(guān)系有一個(gè)明確的認(rèn)識(shí)。在這里我們要知道，作者認(rèn)為遺忘是一種生物在進(jìn)化中適應(yīng)外界殘酷現(xiàn)實(shí)的適應(yīng)性行為，因?yàn)橹挥型袅诉^去的不愉快經(jīng)歷，一個(gè)生命才有可能活得更加生機(jī)勃勃。而這樣的觀點(diǎn)的一種必然推論就是迅速遺忘要優(yōu)于慢速遺忘，因?yàn)橥迷娇炀驮侥苓m應(yīng)外部世界。那么在這里作者就指出用進(jìn)化論適應(yīng)性的觀點(diǎn)來解釋遺忘有局限性。
④ Nevertheless, an evolutionary interpretation might make it difficult to understand how the commonly gradual process of forgetting survived natural selection.
本句的主語(yǔ)是an evolutionary interpretation，謂語(yǔ)might make，而賓語(yǔ)的部分比較復(fù)雜，有一個(gè)形式賓語(yǔ)it，在真正的作賓語(yǔ)的不定式中還有一個(gè)從句how the commonly gradual process of forgetting survived natural selection。
⑤ In thinking about the evolution of memory together with all its possible aspects, it is helpful to consider what would happen if memories failed to fade.
本句的主干是it is helpful to do sth.，真正的主語(yǔ)是to consider這個(gè)不定式，當(dāng)然它里面還包含了一個(gè)帶條件從句的賓語(yǔ)從句。逗號(hào)前面的是一個(gè)狀語(yǔ)。
注意在閱讀的時(shí)候先要抓住主干結(jié)構(gòu)，同時(shí)看清主句中的it是一個(gè)形式主語(yǔ)，指代的是后面的不定式結(jié)構(gòu)。而前面的一個(gè)its應(yīng)該是指memory。
⑥ Another line of thought assumes a memory storage system of limited capacity that provides adaptive flexibility specifically through forgetting.
本句的主干是Another line of thought assumes a memory storage system，在這里assume是一個(gè)及物動(dòng)詞。賓語(yǔ)a memory storage system后面有一個(gè)of引導(dǎo)的介詞詞組和定語(yǔ)從句來修飾它。
注意一些詞的意思，capacity在這里應(yīng)被理解為“容量”，而非“能力”；flexibility是“靈活性”而非“彈性”。
試題解析：
17．【正確答案】 [D]
意為：突然失去記憶力會(huì)導(dǎo)致生存適應(yīng)問題。文章第一段指出，人生許多問題的解決依賴于我們對(duì)過去經(jīng)歷過的事情的記憶。第二段第二、三句指出，如果我們不及時(shí)復(fù)習(xí)或練習(xí)已學(xué)過的東西的話，過一段時(shí)間，我們可能忘記它，這種情況所造成的適應(yīng)性（adaptive）后果也許不太明顯。然而，突然失去記憶力卻會(huì)對(duì)適應(yīng)帶來明顯后果。舉個(gè)例子來說，假如你一覺醒來，發(fā)覺自己失去了一切記億，那樣會(huì)發(fā)生什么呢？
A意為：由于缺乏練習(xí)所造成的遺忘很明顯不利于生存適應(yīng)。這與第二段第二句的意思相反。B意為：如果一個(gè)人突然（all of a sudden）變得健忘，他肯定是非常適應(yīng)生活的。這與第二段第三句表達(dá)的內(nèi)容相反。C意為：逐漸的遺忘過程證明了人的（較強(qiáng)的）適應(yīng)能力。第二段第四句指出，遺忘可以被看作動(dòng)物中自然選擇（natural selection）過程中遺留給人的一種能力。第三段最后一句指出，遺忘（指逐漸的遺忘）似乎對(duì)每個(gè)個(gè)體或整個(gè)物種來說有其生存價(jià)值?？梢?，逐漸的遺忘過程是人在物種間的生存競(jìng)爭(zhēng)過程中形成的，它是人們適應(yīng)外部世界的結(jié)果。C則將人的適應(yīng)能力看作是逐漸遺忘過程的結(jié)果，這顯然顛倒了邏輯關(guān)系。
18．【正確答案】[B]
第三段第三、四句指出，沒有遺忘過程，人就無法適應(yīng)。例如，十年前正確的做法現(xiàn)在未必合適，所以應(yīng)忘記它。對(duì)遺忘很少的人的調(diào)查也表明：他們的日?；顒?dòng)缺乏頭緒。
A意為：他適于生存。這與事實(shí)相反。C意為：他學(xué)習(xí)的能力會(huì)得到加強(qiáng)。這也與事實(shí)相反，事實(shí)是：所學(xué)的東西在大腦中會(huì)無頭緒可尋。D意為：記憶力的進(jìn)化就會(huì)停止。
19．【正確答案】 [A]
意為：遺忘是對(duì)學(xué)習(xí)的一種反應(yīng)。文章最后一段指出，對(duì)記憶力也可以做另一種解釋：記憶的儲(chǔ)存系統(tǒng)總儲(chǔ)量有限，遺忘使這一系統(tǒng)具有了靈活性。這種看法認(rèn)為：在學(xué)習(xí)或存儲(chǔ)（輸入）與遺忘（輸出）之間有一個(gè)不斷調(diào)整過程。事實(shí)上，有證據(jù)表明：遺忘率與學(xué)習(xí)的東西的量直接相關(guān)，這對(duì)現(xiàn)代記憶模式——輸入——輸出保持平衡——提供了證據(jù)。
B意為：記憶儲(chǔ)存系統(tǒng)是一個(gè)輸入輸出完全平衡的系統(tǒng)。根據(jù)原文，確有一種理論認(rèn)為或推測(cè)（assume）記憶儲(chǔ)存系統(tǒng)是一個(gè)輸入輸出平衡的系統(tǒng)，但也僅是假設(shè)而已，另外，exactly一字用得欠妥，太絕對(duì)化。C意為：記憶力是對(duì)遺忘的一個(gè)補(bǔ)償。嚴(yán)格地來講，forgetting與remembering都是memory的一個(gè)組成部分，是一個(gè)部分與整體間的關(guān)系，不能對(duì)照而言D意為：記憶的儲(chǔ)存系統(tǒng)總儲(chǔ)量有限，這是由遺忘造成的。原文只是說遺忘使記憶儲(chǔ)存系統(tǒng)更具適應(yīng)力，不是說它造成了記億儲(chǔ)存系統(tǒng)的有限性。
20．【正確答案】 [B]
本文主要談的是遺忘過程的作用（function），它是人生存適應(yīng)機(jī)制的一個(gè)很重要的過程，這是文章的第二、三、四段所旨在說明的，對(duì)照而言，第一段所談的內(nèi)容（remembering）只不過是這個(gè)討論的引子。
A意為：記憶，記住。C意為：適應(yīng)。D意為：體驗(yàn)。
全文翻譯：
過去的經(jīng)歷會(huì)影響日后的行為，這就表明存在著一種明顯但卻非凡的腦力活動(dòng)——記憶。如果沒有大家稱之為記憶的功能，學(xué)習(xí)便不能發(fā)生。反復(fù)練習(xí)對(duì)記憶有很大影響，可以使人們熟練地演奏鋼琴、背誦詩(shī)歌、乃至總結(jié)和理解這些詞句。用于解決問題或是辨別出有問題存在的所謂的智力行為需要記憶，記憶能力是推理的一個(gè)基本需求。解決任何問題，甚至是識(shí)別問題存在的能力都取決于記憶。最典型的是，決定過街也要憑借許多對(duì)以前經(jīng)歷的記憶。
實(shí)踐（或稱復(fù)習(xí)）就是建立并保持對(duì)某一任務(wù)或所學(xué)材料的記憶。有一段時(shí)間不實(shí)踐，學(xué)到的東西往往就會(huì)忘記（漸進(jìn)性地遺忘）；其適應(yīng)性結(jié)果也就顯得不太明顯。然而戲劇性地突然遺忘的例子也可被看做具有適應(yīng)性。從這個(gè)意義上說，遺忘能力可解釋為動(dòng)物在自然選擇的過程中幸存下來的能力。的確，如果記住一段痛苦的情感經(jīng)歷會(huì)導(dǎo)致嚴(yán)重的焦慮，那么遺忘倒可以使人得到解脫。然而，進(jìn)化論的解釋可能會(huì)使人難以理解普遍的漸進(jìn)遺忘過程是如何在自然選擇中幸存下來的。
在考慮記憶的進(jìn)化及其所有可能的方面時(shí)，思考一下如果記憶不會(huì)消失會(huì)產(chǎn)生什么結(jié)果是很有用處的。顯然，遺忘有助于時(shí)間的定位，因?yàn)榕f的記憶淡忘，新的記憶往往就突出，從而為推算持續(xù)的時(shí)間提供線索。沒有遺忘，適應(yīng)會(huì)受影響，例如，已學(xué)會(huì)的行為十
年前可能是正確的，現(xiàn)在則不然了。有記錄表明，有些人（按一般標(biāo)準(zhǔn)）忘的太少，以致日常生活常混亂不堪。因此遺忘似乎有助于個(gè)體及物種的存活。
另一種思路則假定人的記憶存儲(chǔ)系統(tǒng)儲(chǔ)量有限，這個(gè)系統(tǒng)專門通過遺忘提供適應(yīng)的靈活性。根據(jù)這個(gè)觀點(diǎn)，在學(xué)習(xí)或記憶儲(chǔ)存（輸入）和遺忘（輸出）之間要不斷進(jìn)行調(diào)整。的確，表明個(gè)人的遺忘速度與學(xué)習(xí)東西的多少有直接的關(guān)系。這些數(shù)據(jù)為假定輸入——輸出持衡的當(dāng)代記憶模式提供了明確的證據(jù)。