Question

Life on the Earth is wiped out every 27million years---and we have about 16 million years left until the next extinction, according to scientists.
Research into so-called ‘extinction events’ for our planet over the past 500 million years---twice as long as any previous studies ----has proved that they crop up with metronomic(有節(jié)奏的) regularity .
Scientists from the university of Kansas and the Smithsonian Institute in Washington DC are 99 percent confident that there are extinction every 27 million years.
In the 1980s scientists believed that Earth’s regular extinctions could be the result of a distant dark twin of the Sun, called Nemesis.
The theory was that Nemesis crashed through the Oort cloud every 27 million years and sent a shower of comets in our direction.
The Ocrt cloud is a vast belt of dust and ice that is believed to lie around one light year from the Sun and is the origin of many of the comets that pass through our solar system.
But now scientists claim that the regularity of the mass extinctions actually disproves the Nemesis theory because its orbit would have change over time as it interacted with other stars.
“Fossil data, which motivated the idea of Nemesis, now militate against(妨礙) it,” said the researchers.
The last extinctions event, 11 millions years ago, saw 10 percent of the Earth’s inhabitants (居民) wiped out.
This means there is around 16 million years until the next event takes place, although the graph shows that it occasionally the event takes place up to 10 million years early.
Asteroids(小行星) crashing into the Earth are commonly believed to be one of the main reasons behind mass extinctions like that suffered by the dinosaurs ---the Cretaceous-Tertiary (KT) extinction (白堊-第三紀(jì)滅絕事件).
The extinction wiped out more than half of all species on the planet clearing the way for mammals to become the dominant species(優(yōu)勢物種) on Earth.
The extinction was caused by a massive asteroid slamming into Earth at Chicxulub in Mexico.
The asteroid, which was around 15 kilometers wide, is believed to have hit Earth with a force one billion times more powerful than the atomic bomb at Hiroshima.
小題1: How many years are left until the next extinctions comes? (No more 6 words) (2′)
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小題2:What resulted in the Earth’s regular extinctions according to scientists in the 1980s? (No more than 10words) (2′)
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小題3: What did the last extinction event cause to the Earth? (No more than 10 words)(3′)
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小題4:What’s believed to be one of the main reasons behind mass extinctions like that suffered by the dinosaurs? (No more than 7 words) (3′)
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Answer 1

小題1:About 16million years.
小題2:A distant dark twin of the Sun, called Nemesis.
小題3:10 percent of the Earth’s inhabitants wiped out.
小題4:Asteroids crashing into the earth.

試題分析：文章是科普類短文，介紹地球毀滅的有關(guān)知識，多年來，對于地球的毀滅有著不同的說法，對此的爭論也一直沒有停止。
小題1:細(xì)節(jié)題：從第一段的句子：-and we have about 16 million years left until the next extinction, according to scientists.可知到下一次地球的毀滅還有1千六百萬年， About 16million years.
小題2:細(xì)節(jié)題：從第四段的句子：In the 1980s scientists believed that Earth’s regular extinctions could be the result of a distant dark twin of the Sun, called Nemesis.可知在20世紀(jì)80年代科學(xué)家相信地球定期滅絕是由于遙遠的太陽的黑色的雙胞胎Nemesis.造成的。
A distant dark twin of the Sun, called Nemesis.
小題3:細(xì)節(jié)題：從第九段的句子：The last extinctions event, 11 millions years ago, saw 10 percent of the Earth’s inhabitants (居民) wiped out.可知上一次的毀滅消滅了10%的人類的居民。
10 percent of the Earth’s inhabitants wiped out.
小題4:細(xì)節(jié)題：從第11段的句子：Asteroids(小行星) crashing into the Earth are commonly believed to be one of the main reasons behind mass extinctions like that suffered by the dinosaurs h.可知對于恐龍滅絕的最可能的原因是小行星撞擊地球。 Asteroids crashing into the eart