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雅思阅读题的3大技巧全总结

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做雅思阅读的时候学会总结很重要,今天小编给大家带来了雅思阅读题的3大技巧全总结,希望能帮助到大家,下面小编就和大家分享,来欣赏一下吧。

阅读大作战 雅思阅读题的3大技巧全总结

第一,积累一定的词汇量。大家要正确认识和有效提高词汇量。建议同学们根据考试选材的常见类别进行相应的专题复习,并运用一定的记单词的技巧,单词量是可以在短期内有效提高的。另外,虽然很多同学的单词量还行,但是单词的词形却没有分清楚,虽然说词形对考试来说不是很重要,但是请大家也不要忽略这个问题,在记单词的时候大家多留点心就把词形的问题解决了。

第二,熟悉背景知识。从语言学的角度来看,雅思阅读其实考察的也有背景知识,建议大家多看看国家地理,探索频道,BBC等节目,多积累一些知识,结合考试的常见题材加以学习,若能持之以恒,必有达成。

第三,熟悉语法。语法就相当于英语的经络,如果经脉不通,隐藏的病症就会郁积的越厉害,发作之时如燎原之势必然一发不可收拾。没有语法的词汇就像是脱缰的野马,散落的珍珠,无法够成一个有力的整体,发挥不了原有的效力,希望大家能够活用语法,判断清楚句子的主谓宾,仔细分析句子的结构。

雅思考试阅读模拟练习及答案

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 古生物学家

Aurochs 欧洲野牛

Neanderthal (人类学)尼安德特人,旧石器时代的古人类。

Permafrost (地理)永冻层

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.

Suggested answers and explanations

1. washing, brushing, varnishing 见第一段。

2. handling with gloves / freezing samples ( any one of the two ) 见第二段。

3. losing authentic DNA / being contaminated / contamination ( any one of the three) 见第八段 “Not only is the authentic DNA getting washed out, but contamination is getting washed in” (答being contaminated或 contamination比较保险)

4. they are porous porous 的意思是多孔的。见第八段 “。。。 which can allow water — and contaminants in the form of contemporary DNA — to permeate into the porous bones.”

5. human evolution 见第十五段。其中“shed light on sth”的意思是使某事显得非常清楚,使人了解某事。

6. 4 分别为第四段的“an extinct cattle species, called an aurochs”,即欧洲野牛,已经绝迹;第十一段 “Neanderthal”, 是人类学用语,尼安德特人,旧石器时代的古人类;第十四段“woolly mammoth”和“cave bear”,其中mammoth是猛犸,一种古哺乳动物。

7. T 见第二段。

8. T 见第四段 “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.” 即他们研究的骨化石是一头欧洲野牛身上的。

9. NG

10. F 见第十二段第一、二句话。

11. T 见第十二段末句 “But P bo is keen to see samples of fossils from every major find preserved in line with Geigl’s recommendations — just in case.” 意即为保险起见,Paabo还是非常希望见到用Geigl建议的方法保存的化石样本。“just in case” 的意思是以防万一,就是Paabo对用传统保存处理的化石不放心的意思。

12. A 见第三段。This information就是前一句中 “。。。 just how important conservation practices can be” (to preserve good DNA)。“be hammered”之中hammer一词的意思是不断重复强调。

13. D 面信息。需要理解文章各处关于Geigl和她的同事所作的研究


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