lsat 1 (1) questions

1stzhang

[face=Georgia]15. One of the more reliable methods of determining regional climatic conditions in prehistoric periods is to examine plant pollen trapped in glacial ice during ancient times. By comparing such pollen samples with spores taken from modern vegetation, scientists can figure out approximately what the weather was like at the time of pollen deposition. Furthermore, by submitting the prehistoric samples to radiocarbon dating techniques, we can also determine when certain climatic conditions were prevalent in that portion of the globe.

Which one of the following may be inferred from the information in the passage?

(A) The earth has undergone several glacial periods.

(B) Radiocarbon daring can be corroborated by glacial evidence.

(C) Similarities between prehistoric and contemporary climates do not exist.

(D) Pollen deposition is a fairly continuous process.

(E) Certain flora are reliably associated with particular climatic conditions.

这个题目的答案是E.它是如何从原文中infer出来的?


17. The peculiar evil of silencing the expression of an opinion is that it robs the human race. It takes from posterity, as well as the existing generation, and from those who dissent from the opinion even more than from those who hold it. If the opinion is right, they are deprived of the opportunity of exchanging error for truth; if it is wrong, they lose what is almost as great a benefit: the clearer perception and livelier impression of truth, produced by its collision with error.

Which one of the following best expresses the conclusion presented in the argument?

这个题目比较简单,但是原文似乎有些难度,可以指点一下原文吗?

18. Brushing your teeth regularly, no matter which toothpaste you use, will reduce your chances of tooth decay. Scientists have concluded that, when you brush, you reduce tooth decay by removing the film of plaque that forms on teeth and gums. So, you can forget about fluorides: brush your teeth carefully and say goodbye to cavities.

Which one of the following is a criticism of the reasoning in the argument?

(A) Brushing with fluoride toothpaste has been shown to reduce tooth decay.

(B) The fact that brushing will reduce tooth decay does not show that fluorides are of no value.

(C) Few people adequately remove plaque by brushing.

(D) People have plaque on their teeth most of the time.

(E) Scientists have been wrong about fluorides.

这个题目答案是B,我当时在B/E之间犹豫了.但是我没有明白B的真正的含义主要是fluorides are of no value应该如何精确理解?



If the city council institutes new parking regulations, city revenues will surely increase, since studies have conclusively shown that, if such parking regulations are put into effect, there is an increase in parking violations, and an increase in parking violations will result in a greater number of parking fines collected.

21. Which one of the following is closest, in terms of its logical features, to the reasoning used in the argument above?

(A) Last year’s increase in revenues can be easily explained. That was the year the city council instituted new parking regulations. No doubt the new law brought with it an increase in the number of parking violations.

(B) If taxes were increased, this act would naturally result in increased revenues for the city, and increased revenues would make some desirable social programs possible. So, if taxes were increased, some desirable social programs would become possible.

(C) Henry says that, if the city council goes into closed session, an important matter of personnel policy is being discussed. However, no personnel matters were discussed at the council meeting, so if Henry is right, the council did not go into closed session.

(D) All cars parked on the north side of the street were ticketed last night, and the same cars were towed away this morning. So beware A car ticketed in this city also gets towed away.

(E) Allen says that, if the city council institutes new parking regulations, it is unlikely that revenues for the city will increase. If Allen is right, then the parking regulation plan should not be instituted.

这个题目的问法是什么意思?请指点一些思路?[/face]

lyricling

Let me try.

1,　Lsat1(上)15

其实这道题考的是assumption。比较难的归纳题大多数都是这种“假设型”的归纳题。也就是原文给出一个推理，在承认推理正确的前提下infer　就是要找出使原文推理成立的那个隐含的必要条件。

原文推理：
（1）比较古代pollen与现代spores →　可以推知 pollen 时代的气候
（2）用radiocarbon方法分析pollen(prehistoric samples)　→　可以推知certain climatic conditions 在当地盛行的时间
A: several glacial periods 原文没有提及，无关项
B：冰川证据可以证实radiocarbon dating　原文也没有讲过
C：史前气候与当代气候的相似性不存在　推不出
D：continuous process　原文没有提及
E：某些植物群落与特定气候相关。

本项是原文推理（2）的假设，如果植物群落与气候不相关，那radiocarbon　如何能够利用pollen 推知certain climatic conditions 在当地盛行的时间呢？所以原文推论成立，则E必然成立。

2,  Lsat1(上)17　我只能试着将大意讲一讲。

结论：钳制言论表达的罪恶在于它剥夺了human race(不知道是不是人权的意思，没查着)。
证据：钳制言论对后代，对当代以及对那些某种言论的反对者的危害大于那些持有这种言论的人。（2）如果某种言论是正确的，（钳制言论）也得失参半：因为真理是越辩越明的。

我做这种中心思想归纳题的时候，都是把它当作句子作用题在做。原文中除了结论就是证据。如果文中没有however,这种题的中心思想一般都在头或尾，如果有however，中心思想就在however后。

3，B项的意思是“刷牙能够防止虫牙并不能说明氟不起作用”

4，逻辑类似题，问的是选项中哪一个的逻辑论证方法与原文类似。

原文推理（三段论）
结论：new parking regulations(A)　→　revenues 上升(C)
证据：new parking regulations(A) → violations increase (B) → fines(= revenues) increase (C)

B项:
证据：tax increase(A) → revenues increase(B) → programs possible(C)
结论：tax increase(A) → programs possible(C)

很类似吧？

1stzhang

谢谢lyricling 认真详细地回答！

lyricling

不谢！你也给了我很多帮助嘛。
互相帮助，嘻嘻！