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标题: OG23 143 [打印本页]

作者: flyingceleste 时间: 2005-12-8 08:10
标题: OG23 143

Passage 23

New observations about the age of some globular

clusters in our Milky Way galaxy have cast doubt on a

long-held theory about how the galaxy was formed. The

Milky Way contains about 125 globular clusters (com-

(5)pact groups of anywhere from several tens of thousands

to perhaps a million stars) distributed in a roughly

spherical halo around the galactic nucleus. The stars in

these clusters are believed to have been born during the

formation of the galaxy, and so may be considered relics

(10)of the original galactic nebula, holding vital clues to the

way of the formation took place.

The conventional theory of the formation of the galaxy

contends that roughly 12 to 13 billion years ago the

Milky Way formed over a relatively short time (about

(15)200 million years) when a spherical cloud of gas col-

lapsed under the pressure of its own gravity into a disc

surrounded by a halo. Such a rapid formation of the

galaxy would mean that all stars in the halo should be

very nearly the same age.

(20) However, the astronomer Michael Bolte has found

considerable variation in the ages of globular clusters.

One of the clusters studied by Bolte is 2 billions years

older than most other clusters in the galaxy, while

another is 2 billion years younger. A colleague of Bolte

(25)contends that the cluster called Palomar 12 is 5 billion

years younger than most other globular clusters.

To explain the age differences among the globular

clusters, astronomers are taking a second look at

“renegade” theories. One such newly fashionable theory,

(30)first put forward by Richard Larson in the early 1970’s,

argues that the halo of the Milky Way formed over a

period of a billion or more years as hundreds of small

gas clouds drifted about, collided, lost orbital energy,

and finally collapsed into a centrally condensed elliptical

(35)system. Larson’s conception of a “lumpy and turbulent”

protogalaxy is complemented by computer modeling

done in the 1970’s by mathematician Alan Toomre,

which suggests that closely interacting spiral galaxies

could lose enough orbital energy to merge into a single

galaxy.

143. The author of the passage puts the word “renegade” (line 29) in quotation marks most probably in order to

(A) emphasize the lack of support for the theories in question

(B) contrast the controversial quality of the theories in question with the respectable character of their formulators

(D) ridicule the scientists who once doubted the theories in question (E)

(E) indicate that the theories in question are no longer as unconventional as they once seemed

The best answer is E. To describe a theory as “renegade” is to suggest that it is unconventional.

However, the author puts the word “renegade” in quotation marks (line 29) when using it to

describe theories that, the author says, are “newly fashionable” (line 29). The use of quotation

marks with this word in this way serves to indicate that the theories in question are no longer as

unconventional as they once seemed. There is nothing in the passage to suggest that any of the

other choices describe goal of the author.

GMAT里引号作用记得有2个，一个是反语讽刺，一个是强调，这里为啥不能选D哪？哪里体现这个理论是“newly fashionable”了？renegade不是变节者得意思吗？

作者: flyingceleste 时间: 2005-12-8 22:25
是不是问得太幼稚了

作者: flyingceleste 时间: 2005-12-9 07:43
确实问了个弱智问题，昨晚突然发觉了定位处，看漏了

作者: hhl3000 时间: 2006-1-22 13:55
同问

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