Question

（This selection was originally published in 1992. Pluto （冥王星） is no longer classified as a planet.）

Pluto is in many ways the strangest of the planets. It is small and has a large moon（called Charon）. Its orbit（轨道） is unusual, which may cause it to have seasons in the sense that when it is close to the sun, the liquid （液体）methane（甲烷）on its surface boils to form a kind of atmospheric haze（烟雾）. When the planet moves farther away from the sun, it starts to snow solid（固体） methane.

Pluto is not dark. Despite its great distance from the sun, the surface of Pluto is probably as bright as a moonlit night on Earth. The reason is all that methane, which is as white as newly fallen snow.

The discovery of Pluto was more accident than design. The American astronomer Percival Lowell had predicted the existence of a ninth planet（he called it Planet X）based on what he took to be irregularities in the orbit of Neptune. Today astronomers argue that these "irregularities" weren't real, but the result of instrumental error. Nevertheless, Lowell produced predictions about where Planet X ought to be（although, to be honest, the predictions changed occasionally when he redid the calculations）.In any case, in 1930 Clyde Tombaugh, doing a systemic sky survey that would have found the planet no matter where it was, discovered the planet we now call Pluto. By coincidence, its position was pretty close to where Lowell's last prediction said it should be. Was it just luck? We'll never know．

1.On Pluto's surface, liquid methane boils to form an atmospheric haze, which would be most similar to ____.

A. light B. darkness

C. liquid D. steam（水蒸气）

2.What effect is produced by including the question "Was it just luck?" at the end of the text?

A. The question encourages the reader to think about why Pluto is a strange planet．

B. The question encourages the reader to think about how planets are discovered．

C .The question suggests that all discoveries are luck, not just design．

D. The question suggests that other planets were found in different ways．

3.What contributes to the brightness of Pluto?

A. Methane on its surface. B. Its great distance from the sun.

C. Light from its moon, Charon. D. Its closeness to the sun.

4.The text mainly wants to ____．

A. give a brief introduction of Pluto

B. talk about the discovery of Pluto

C. prove the exact position of Pluto

D. describe the strangeness of Pluto

 

Answer 1

1.D

2.B

3.A

4.A

【解析】

试题分析: 本文讲述冥王星与其他行星的不同。

1. 细节理解题。根据第二段提到when it is close to the sun, the liquid （液体）methane（甲烷）on its surface boils to form a kind of atmospheric haze（烟雾）. When the planet moves farther away from the sun, it starts to snow solid（固体） methane.

当它接近太阳，其表面的液体（液体）甲烷沸腾并形成一种大气灰霾（烟雾）。当它离太远稍远些时，它开始冷却成固体甲烷落下。 故选D项。

2.The discovery of Pluto was more accident than design冥王星的发现过程更多地是出于偶然，可推测选 B项。

3. 细节理解题。根据第三段Despite its great distance from the sun, the surface of Pluto is probably as bright as a moonlit night on Earth. The reason is all that methane, which is as white as newly fallen snow.可知因为甲烷，冥王星才如同地球上的月夜那样地明亮，故选A项。

4. 主旨大意题；由每段的第一句可知，全文讲述了冥王星的相关情况故选A项。

考点：科普阅读