Question

Planet Earth would be a scary place for humans if dinosaurs still ruled the world.

Though there are still some traces of life from the Jurassic Period, the Age of Dinosaurs more than 65 million years ago.

This mass extinction is believed to be the result of an asteriod（小行星）hitting Earth. A new report by the journal Biological Reviews called " The Extinction of Dinosaurs” concludes that this impact was, indeed, the cause of the dinosaurs’ demise. But the space blast(爆炸) wasn't the only reason these creatures aren't still around today.

Dinosaurs need food to survive. Meat-eating monsters like the Tyrannosaurus Rex(霸王龍) were at the top of the food chain, and fed off plant eaters like the horned Triceratops (三角恐龍). These herbivores (食草動(dòng)物) were decreasing in population after the asteroid hit Earth, which left the meat-eating species less food to survive on. “In any ecosystem where you remove links to key species, that community has problems," Richard Butler, one of the review's authors, told National Ceographic.

While the herbivore population was going down, Earth's temperatures were rising when volcanoes erupted. Hot vapors and gases began wiping out some of the dinosaur population and weakening the survivors.

These changes made the asteroid's impact especially powerful. It caused more volcanoes to erupt, heated up Earth's atmosphere, and led to a sharp drop in the level of oxygen in the oceans.

With the dinosaurs gone, mammals(哺乳動(dòng)物) began to evolve into bigger and more diverse species. Many animals we see today, like birds, sharks, and even some cats and dogs, appeared after the asteroid hit Earth. But none rule Earth quite like the dinosaurs did..

1. Which of the following words can replace the underlined word’’ demise" in Paragraph 2?

A. Death. B. Evolvement.

C. Presence. D. Decrease.

2. According to what Richard Butler said, what caused dinosaurs to die out?

A. A shortage of clean water.

B.A break in the food chain.

C. A small variety of animals.

D. The constant warming climate.

3. What was the negative effect of the asteroid hitting Earth?

A. Oceans became too hot for animals.

B. There was less oxygen in the oceans.

C. Earth's climate became violent.

D. The majority of the plants gradually died out.

4. The text is mainly about .

A.the evolvement of mammals on Earth

B.the gradual process of climate change

C.the importance of the balance of ecosystem

D.the cause of the extinction of the dinosaurs

Answer 1

1.A

2.B

3.B

4.D

【解析】

試題分析：如果恐龍還是世界的霸主的話，地球?qū)θ祟悂碚f會(huì)是個(gè)令人恐懼的地方。本文從小行星撞擊地球的影響，食物鏈的斷裂和致命的氣候變化三方面闡述了導(dǎo)致恐龍死亡的原因。。

1.小題1】猜測詞義題：從第二段的內(nèi)容：可知《生物學(xué)研究》的一篇名為“恐龍的滅絕”新研究斷定：“小行星撞擊地球的影響，其實(shí)是導(dǎo)致恐龍死亡的原因。A. Death. 死亡 B. Evolvement.進(jìn)化 C. Presence.出現(xiàn) D. Decrease.減少，可知選A。

2.小題2】細(xì)節(jié)理解題：從第三段得知：恐龍彼此依靠而存活。這些食肉的怪獸，如食物鏈頂端的霸王龍，以三角龍類的食草動(dòng)物為生。這些食草動(dòng)物在小行星時(shí)代數(shù)量遞減，使得食肉動(dòng)物的難以生存。因此Richard Butler認(rèn)為是食物鏈的斷裂導(dǎo)致恐龍滅絕。選B。

3.小題3】推理判斷題：根據(jù)第五段得知這些環(huán)境因素促使小行星的影響變得尤其強(qiáng)大。它使更多火山噴發(fā)，地球大氣溫度升高，導(dǎo)致海洋中的氧含量急劇下降。答案是B。

4.小題4】主旨大意題。根據(jù)文章從小行星撞擊地球的影響，食物鏈的斷裂和致命的氣候變化三方面闡述了導(dǎo)致恐龍死亡的原因。得知選D。

考點(diǎn)：科普類文章