恐龙是怎么灭绝的
恐龙是怎么灭绝的？你可能听说过是跟陨石撞地球有关系，那恐龙是不是被砸死的？当然不是啦。主要是因为陨石撞上地球以后，森林被大火摧毁，尘埃笼罩天空，未在撞击和其直接影响下死去的恐龙也在之后的余波中渐渐消亡。
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Time flies, millions of years pass and as the continents keeps on drifting, the Earth begins to resemble more what it is today. Species emerge, evolve, disappear, nature never stops changing. 时光飞逝，数百万年过去了，大陆继续漂移，地球与如今越来越相似。物种出现、进化，又消亡，大自然的变化从不停歇。
★ drift vi.漂移
★ resemble v.与…类似
★ emerge v.出现
★ evolve v.进化
We are in North America. Flying reptiles reach their apogee with the Quetzalcoatlus, a pterosaur as wide as a small plane. 我们在北美洲，飞行的爬行动物达到顶峰，这是风神翼龙，一种翼展如同小型飞机的翼龙。
★★ reptile n.爬行动物
★★★ apogee n.最高点
★★★ pterosaur n.翼龙
Apart from flight, this reptile has nothing in common with birds. And evolution gave it nothing to survive the impending dramatic events. 除了飞行，这种爬行动物与鸟类别无相同之处，不过进化没有赋予它在之后剧变中生存下来的能力。
★ evolution n.进化
★★★ impending a.即将发生的
★ dramatic a.巨大而突然的
Several factors could have contributed to the demise of dinosaurs. Mammals became bigger and more competitive. Drifting, isolated continents touched each other. New rival race appeared. New disease spread. Climate was growing colder, possibly because of increased volcanic activity. 恐龙的消亡可能归结到几个因素。哺乳动物变得更大更有竞争力，漂移的孤立大陆又相互接壤，新竞争种类的出现，新型疾病的传播，气候持续变冷，这可能是因为火山活动的增加。
★ contribute to 导致
★★★ demise n.消亡
★★ mammal n.哺乳动物
★★ competitive a.竞争的
★★ isolated a.孤立的
★ rival a.竞争的
5 million years before the end of the dinosaur era, the volcanoes of the world became much more active. The air was unbreathable in many places. Vegetation suffered from the acid rain and also from the darkened and dust-filled skies. 在恐龙时代结束前的5百万年前，地球上的火山变得活跃得多。很多地方的空气无法呼吸，植物遭受酸雨的打击，还要忍受遍布烟尘的阴暗天空。
★ era n.时代
★ unbreathable a.不宜呼吸的
★★ vegetation n.植被
★ acid rain 酸雨
This comet is as big as Mount Everest, covers the distance from the Moon to the Earth in two hours, cuts through our atmosphere in two seconds. 这颗彗星跟珠穆朗玛峰一样大，飞过地球和月球间的距离只用两小时，穿过大气层只用了两秒时间。
★★★ comet n.彗星
★★★ Mount Everest 珠穆朗玛峰
It hits the Earth near today’s Yucatan Peninsula in Mexico. All the forests in North and South America are destroyed by fire. Already weakened, dinosaurs are the animals that suffer most. If they don’t die as the result of the impact and its immediate consequences, they will die gradually in the aftermath. 它在如今墨西哥尤卡坦半岛处撞上地球，所有北美洲和南美洲的森林都被大火摧毁，已经被削弱的恐龙在这次灾难中受到的打击最大，在撞击和其直接影响下没有死去的恐龙也在之后的余波中渐渐消亡。
★★ peninsula n.半岛
★ impact n.撞击，冲击
★★★ aftermath n.余波
It’s difficult to imagine how mammals could’ve evolved alongside large dinosaurs, if they hadn’t become extinct, maybe we just wouldn’t be here. 很难想象哺乳动物与巨大的恐龙并肩进化，要是它们没有灭绝，也许我们今天都不会在这里。
★★ mammal n.哺乳动物
★ evolve v.进化
★ alongside prep.与……同时
★★ extinct a.灭绝的
注：一星词汇为四级难度，二星词汇为六级、考研难度，三星词汇为雅思、托福及以上难度，大家根据自己的考试要求选择性学习，参考所列词句自由做笔记，学单词、涨知识。建议准备一个专门的本子，日积月累，这会是不小的收获！
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