篇章目的题—考前小测1

1.The main purpose of the passage is to

A.describe how squadrons of planes can save fuel by flying in a V formation.

B.discuss the effects of downdrafts on birds and airplanes.

C.explain research conducted to study why some birds fly in a V formation.

D.illustrate how birds sense air currents through their feathers.

Anyone watching the autumn sky knows that migrating birds fly in a V formation, but scientists have long debated why. A new study of ibises finds that these big-winged birds carefully position their wingtips and sync their flapping, presumably to catch the preceding bird’s updraft—-and save energy during flight. (2016-10-U.S.)

2. The primary purpose of the passage is to

A.discuss findings that offer a scientific explanation for the Venus flytrap’s closing action.

B.present research that suggests that the Venus flytrap’s predatory behavior is both complex and unique among plants.

C.identify the process by which the Venus flytrap’s closing action has evolved.

D.provide a brief overview of the Venus flytrap and its predatory behavior.

Scientists have been puzzled by these questions ever since John Burdon-Sanderson’s early report on the physiology of the Venus flytrap in 1882. A century later, Dieter Hodick and Andreas Sievers at the University of Bonn in Germany proposed that the flytrap stored information regarding how many hairs have been touched in the electric charge of its leaf. Their model is quite elegant in its simplicity. In their studies, they discovered that touching a trigger hair on the Venus flytrap causes an electric action potential…. (2017-01-U.S.)

3. The main purpose of the passage is to

A.discuss how metaphors are used in depictions of crime.

B.demonstrate how metaphors shape people’s perceptions.

C.illustrate how metaphors can undermine social policies.

D.show how metaphors can be used to enhance storytelling.

That is the power of metaphor —a power so subtle we barely notice how much it impacts our thinking, Researchers Paul Thibodeau and Lera Boroditsky from Stanford University demonstrated how influential metaphors can be through a series of five experiments designed to tease apart the “why” and “when” of a metaphor’s power. (2017-03-U.S.)

4. The main purpose of the passage is to

A.discuss research into the origins of ancient European farmers.

B.resolve a debate about when farming first appeared in Europe.

C.consider a study of the farming methods of ancient Europeans.

D.explain the conflict between archaeological and genetic evidence about the first European farmers.

The rise of agriculture in the Middle East, nearly 11,000 years ago, was a momentous event in human prehistory. But just how farming spread from there into Europe has been a matter of intense research. A new study of ancient DNA from 5,000-year-old skeletons found in a French cave suggests that early farmers entered the European continent by at least two different routes and reveals new details about the social structures and dairying practices of some of their societies. (2017-05-U.S.)

5. The main purpose of the passage is to 

A.compare the findings of a series of historic scientific experiments that show plants can recall learned responses.

B.discuss a scientific study that advances an earlier arguments about the capability of plants to learn and recall.

C.argue that a debunked hypothesis about how plants learn must be reconsidered in light of new evidence.

D.examine the means by which plants learn, retain, and transmit information.

More than a century ago Bengali polymath Sir Jagadish Chandra Bose posited that plants could feel, learn and remember, and more recent studies have confirmed they can store and recall biological data. But research by Monica Gagliano of the University of Western Australia and three fellow scientists goes much further. This study, published in Oecologia, offers proof that plants not only learn from experience, but remember what they have learned over relatively long periods. (2017-08-U.S.)

大家不难发现,这五道题是一类的题目,主要考查篇章目的,即作者为什么写这篇文章。解这类题目有一个小技巧,但技巧只限科技文和社科文才能使用。

科技类文章在说明整个的研究过程之前会概括该文章要写的内容,能够找出这一句或一段的概括的话就能直接判断全文的目的了。通常这句话是“某某大学的谁在什么时候做了一个关于什么的研究”,研究的内容可能出现在这句话的前后。

了解完这段小技巧,你可以重新做一下前面五道题,五道题答案是:CABAB。

段落目的题 —- 考前小测2

1.The main purpose of the last paragraph is to 

A.discuss the progress being made in studies of perennial plants.

B.persuade farmers to begin growing perennial pants

C.illustrate how perennial plants can help feed people in Nepal.

D.outline the positive characteristic of perennial plants.

The perennial wheat-wheatgrass hybrid now growing at the Land Institute can already be made into flour. Yields are too low to compete with annual wheat in Kansas— but maybe not in Nepal, which has steeper slopes and a harsher climate, and where a researcher is now testing perennial hybrids in small plots. Amber waves of perennial grain may be decades away, but the emergence of cheap DNA sequencing is allowing plant breeders to work much faster than they used to. Buckler thinks that for a tiny fraction of the billions spent annually on corn research, one could create field-testable perennial corn in as little as ten years. “I think we should take a shot at revolutionizing agriculture,” he says. (2016-06-U.S.)

2. The author includes the seventh paragraph (line 68-74) most likely to 

A.advance reservation about the design of the experiment explored in the passage.

B.suggest that questions regarding the learning ability of plants remain.

C.offer a potential resolution to an ongoing debate among scientists who study plants.

D.imply that some conclusions about the ability of plants to learn may have been premature.

Dr. Gagliano and her colleagues admit that they do not conclusively know how plants — lacking brains or neutral tissues — learn and remember. Calcium-based cellular signaling is one possible explanation, as is the processing of information by cells via ion flows —- plants have well-established pathways to transmit information via electrical signals. (2017-08-U.S.)

3 In Passage 2, what is the main purpose of the third paragraph (lines 59-65) 

in relation to the passage’s discussion of Neukum?

A.to concede that Neukum’s study is controversial.

B.to explain the main issues addressed by Neukum’s research.

C.to describe a significant implication of Neukum’s findings.

D.to discuss a possible error in Neukum’s analysis.

If this is true, Mar’s reputation as a once-habitable planet that may still harbour microscopic life is at stake. A billion years might well have been long enough for life to emerge, but the speed with which those conditions vanished would have made it much more difficult for that early life to truly establish itself. (2017-03-U.S.)

4. The main purpose of paragraph 8 is to

A.reintroduce a topic mentioned earlier in the passage and explore it in greater detail.

B.transition from a set of facts to a larger context in which those facts can be considered.

C.anticipate and refute a potential objection to the author’s argument.

D.acknowledge the limitations of a position but suggest that those limitations are irrelevant.

It makes sense that T. rex would grow this way, experts say. Several lines of evidence suggest that dinosaurs had a higher metabolism and faster growth rates than living reptiles do. Previous work by Erickson showed that young dinosaurs stepped up the pace of growth, then tapered off into adulthood; reptile, in contrast, grow more slowly, but they keep at it for longer. (2017-03-U.S.)

5. Which choice best describes how the last paragraph functions in the passage?

A.It identifies the need for research that builds on that described in the passage.

B.It summarizes the key observations that are presented in the passage.

C.It challenges the validity of the explanations offered by the scientists discussed in the passage.

D.It presents an alternative explanation for a phenomenon that is noted in the passage.

It also remains to be shown whether the observed pattern holds for less fragmented metapopulations. The Plantago metapopulation studied by Jousimo et al. on the Aland archipelago in Finland is highly fragmented; do metapopulations with higher rates of migration between populations show similar patterns? (2016-12-U.S.)

上面五道题通过题干不难看出都是在考作者写某一段的目的,这种题目在科技和社科的文章中总是会考三个地方,一个是research前的段落作用,第二个是research的结果段,第三个是结果段后的段落作用。下面我们就来分析最复杂的第三种情况,即结果段之后都会出现哪些内容。

1.application (应用:实验的结果的用处,即得到的结果可以用来干什么。)

2.significance(实验的意义,通常通过某些科学家的评价来体现)

3.limitations (实验的局限,科学研究肯定都会有一些为解决或是有问题的地方)

4.progress and development in the field (在所研究领域的其他进步和发展)

5.put the results into larger context to consider or compare (得出的研究结果置于更大的范围去考虑,比如某一特定植物的某种属性是否适用到所有类似植物中。这一点在真题至少考过三次了,参考:2017-03-U.S. P3/2016-10-U.S. P5/ 2017-11-U.S. P5)

6.implication (possible future effect,即如果结果是正确的,会对某某东西产生的影响)

7.to raise further questions (某个结果所带来的其他问题)

8.to identify problems that to be yet resolved (研究出来的东西还有哪些问题,这个跟limitations会有一些重合)

通过上述对结果段之后会出现哪些内容的分类,想必大家都会清晰很多,回去再做一遍五道题,也许会有不同的结果。答案是:ABCBA。

了解科技文的篇章对解答科技文非常有帮助,今天的两个小技巧希考有用,明天我们还会讲解另外两种目的题目的解法,大家敬请期待。


最新SAT精校版打包真题+答案(更新到2021年5月)

欢迎扫码添加TD客服微信
并发送关键字「SAT真题」领取
持续更新哦~