雅思閱讀題的3大技巧全總結

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做雅思閱讀的時候學會總結很重要，今天小編給大家?guī)砹搜潘奸喿x題的3大技巧全總結，希望能幫助到大家，下面小編就和大家分享，來欣賞一下吧。

閱讀大作戰(zhàn) 雅思閱讀題的3大技巧全總結

第一，積累一定的詞匯量。大家要正確認識和有效提高詞匯量。建議同學們根據(jù)考試選材的常見類別進行相應的專題復習，并運用一定的記單詞的技巧，單詞量是可以在短期內有效提高的。另外，雖然很多同學的單詞量還行，但是單詞的詞形卻沒有分清楚，雖然說詞形對考試來說不是很重要，但是請大家也不要忽略這個問題，在記單詞的時候大家多留點心就把詞形的問題解決了。

第二，熟悉背景知識。從語言學的角度來看，雅思閱讀其實考察的也有背景知識，建議大家多看看國家地理，探索頻道，BBC等節(jié)目，多積累一些知識，結合考試的常見題材加以學習，若能持之以恒，必有達成。

第三，熟悉語法。語法就相當于英語的經(jīng)絡，如果經(jīng)脈不通，隱藏的病癥就會郁積的越厲害，發(fā)作之時如燎原之勢必然一發(fā)不可收拾。沒有語法的詞匯就像是脫韁的野馬，散落的珍珠，無法夠成一個有力的整體，發(fā)揮不了原有的效力，希望大家能夠活用語法，判斷清楚句子的主謂賓，仔細分析句子的結構。

雅思考試閱讀模擬練習及答案

Don’t wash those fossils!

Standard museum practice can wash away DNA.

1. Washing， brushing and varnishing fossils — all standard conservation treatments used by many fossil hunters and museum curators alike — vastly reduces the chances of recovering ancient DNA.

2. Instead， excavators should be handling at least some of their bounty with gloves， and freezing samples as they are found， dirt and all， concludes a paper in the Proceedings of the National Academy of Sciences today.

3. Although many palaeontologists know anecdotally that this is the best way to up the odds of extracting good DNA， Eva-Maria Geigl of the Jacques Monod Institute in Paris， France， and her colleagues have now shown just how important conservation practices can be. This information， they say， needs to be hammered home among the people who are actually out in the field digging up bones.

4. Geigl and her colleagues looked at 3，200-year-old fossil bones belonging to a single individual of an extinct cattle species， called an aurochs. The fossils were dug up at a site in France at two different times — either in 1947， and stored in a museum collection， or in 2004， and conserved in sterile conditions at -20 oC.

5. The team’s attempts to extract DNA from the 1947 bones all failed. The newly excavated fossils， however， all yielded DNA.

6. Because the bones had been buried for the same amount of time， and in the same conditions， the conservation method had to be to blame says Geigl. “As much DNA was degraded in these 57 years as in the 3，200 years before，” she says.

Wash in， wash out

7. Because many palaeontologists base their work on the shape of fossils alone， their methods of conservation are not designed to preserve DNA， Geigl explains.

8. The biggest problem is how they are cleaned. Fossils are often washed together on-site in a large bath， which can allow water — and contaminants in the form of contemporary DNA — to permeate into the porous bones. “Not only is the authentic DNA getting washed out， but contamination is getting washed in，” says Geigl.

9. Most ancient DNA specialists know this already， says Hendrik Poinar， an evolutionary geneticist at McMaster University in Ontario， Canada. But that doesn’t mean that best practice has become widespread among those who actually find the fossils.

10. Getting hold of fossils that have been preserved with their DNA in mind relies on close relationships between lab-based geneticists and the excavators， says palaeogeneticist Svante P bo of the Max Planck Institute for Evolutionary Anthropology in Leipzig， Germany. And that only occurs in exceptional cases， he says.

11. P bo’s team， which has been sequencing Neanderthal DNA， continually faces these problems. “When you want to study ancient human and Neanderthal remains， there’s a big issue of contamination with contemporary human DNA，” he says.

12. This doesn’t mean that all museum specimens are fatally flawed， notes P bo. The Neanderthal fossils that were recently sequenced in his own lab， for example， had been part of a museum collection treated in the traditional way. But P bo is keen to see samples of fossils from every major find preserved in line with Geigl’s recommendations — just in case.

Warm and wet

13. Geigl herself believes that， with cooperation between bench and field researchers， preserving fossils properly could open up avenues of discovery that have long been assumed closed.

14. Much human cultural development took place in temperate regions. DNA does not survive well in warm environments in the first place， and can vanish when fossils are washed and treated. For this reason， Geigl says， most ancient DNA studies have been done on permafrost samples， such as the woolly mammoth， or on remains sheltered from the elements in cold caves — including cave bear and Neanderthal fossils.

15. Better conservation methods， and a focus on fresh fossils， could boost DNA extraction from more delicate specimens， says Geigl. And that could shed more light on the story of human evolution.

(640 words nature )

Glossary

Palaeontologists 古生物學家

Aurochs 歐洲野牛

Neanderthal (人類學)尼安德特人，舊石器時代的古人類。

Permafrost (地理)永凍層

Questions 1-6

Answer the following questions by using NO MORE THAN THREE WORDS for each answer.

1. How did people traditionally treat fossils?

2. What suggestions do Geigl and her colleagues give on what should be done when fossils are found?

3. What problems may be posed if fossil bones are washed on-site? Name ONE.

4. What characteristic do fossil bones have to make them susceptible to be contaminated with contemporary DNA when they are washed?

5. What could be better understood when conservation treatments are improved?

6. The passage mentioned several animal species studied by researchers. How many of them are mentioned?

Questions 7-11

Do the following statements agree with the information given in the passage? Please write

TRUE if the statement agrees with the writer

FALSE if the statement does not agree with the writer

NOT GIVEN if there is no information about this in the passage

7. In their paper published in the Proceedings of the National Academy of Sciences ， Geigl and her colleagues have shown what conservation practices should be followed to preserve ancient DNA.

8. The fossil bones that Geigl and her colleagues studied are all from the same aurochs.

9. Geneticists don’t have to work on site.

10. Only newly excavated fossil bones using new conservation methods suggested by Geigl and her colleagues contain ancient DNA.

11. Paabo is still worried about the potential problems caused by treatments of fossils in traditional way.

Questions 12-13

Complete the following the statements by choosing letter A-D for each answer.

12. “This information” in paragraph 3 indicates：

[A] It is critical to follow proper practices in preserving ancient DNA.

[B] The best way of getting good DNA is to handle fossils with gloves.

[C] Fossil hunters should wear home-made hammers while digging up bones.

[D] Many palaeontologists know how one should do in treating fossils.

13. The study conducted by Geigl and her colleagues suggests：

[A] the fact that ancient DNA can not be recovered from fossil bones excavated in the past.

[B] the correlation between the amount of burying time and that of the recovered

DNA.

[C] the pace at which DNA degrades.

[D] the correlation between conservation practices and degradation of DNA.

雅思閱讀題的3大技巧全總結

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