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开发和利用清洁而又高效的新能源,是21世纪人类面临的重要课题.
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    You probably know many of the things that you can do with the hundreds of different muscles in your body. But have you ever thought about how the muscles in an animal's body are different from yours? An animal's muscles are made to do the things that are most important for its life.

    Lions are hunters. They depend on their ability to catch other animals. Lions must be fast in order to catch their prey(猎物). The powerful muscles in their back legs allow them to run at speeds of more than 30 miles per hour. They can also jump a distance of more than 35 feet. The strong muscles in their front legs help them catch their prey.

    Snakes also use their muscles for hunting prey and for movement, but their muscles work in very different ways than lions' do. Because snakes do not have any legs, they use their muscles to push against the ground or other objects to move themselves forward. Their muscles also allow them to eat things that seem much too large. For example, a snake may eat an egg that is larger than the width of its body. How does this happen? The snake's strong neck muscles work together to push the egg down the mouth.

    The elephant's long nose has a lot of muscles. Scientists believe that the nose alone has more than 100,000 muscles! This is because the elephant uses its nose much in the same way that people use their hands and fingers. Even though the nose is large, it can perform surprisingly tasks. For example, an elephant can pick up a small leaf from the ground. The nose can also be a powerful tool. An elephant can use its nose to pick up a tree by its roots or even to lift a baby elephant.

    The great muscles of these animals seem pretty unbelievable. But the muscles in your body work exactly the way you need them to. After all, it might be fun to be able to jump a distance of 30 feet, but as a human being, there is just not much need for it.

同类题2

阅读下面文章,完成题目。
                                                                                                        生 命 赋
    ①我常常在大自然中看到种种生命的奇观。
    ②挺拔的巨树,葱茏的森林,绿色的草原,成熟的庄稼,盛开的野花,望着它们,或徜徉其中,那种洋溢着的博大的生命力,常常催发我爆发我的生命激情,在体内蔓延,奔涌,激荡。
    ③但是,有一些更细微更不显眼的现象,往往特别作用于我的心尖和神经末梢,引起我异常深刻的震颤。
    ④早春,当冰尚未完全消融、万物尚未苏醒的时候,柳树的枝条还是铁灰色,可如小米粒般的新芽已经顶着严寒冒出来。它就是报春的最早的使者,万木峥嵘的自然之春就是从它开始的。
    ⑤当柳芽发出不久,在棉花地里,可以看见棉芽冲破柔韧的壳子,一个个钻出地面,遍地都写着两个字:突破。
    ⑥麦收过后,麦地里新播种的大豆,不几天工夫,从薄薄的透明的外衣中露出茁壮的一点胚芽,探头顶破地表,满地像是用五线谱写成的生命第一乐章。它预示着,也开始演奏着一部生命交响乐;活泼泼的胖乎乎的豆苗,无边无际的宜人眼目的豆绿色波浪,成熟的金黄色的小山。
    ⑦我害怕看见花蕾。特别是那种已露出一点亮色,将要绽开的花蕾。我一看见它,就如痴如醉,就完全被它吸引,不顾一切地去做生命瑰丽巅峰的想象:经过长久的默默经营、吮吸、积累,所积蓄的全部精华、神采、光辉,就要在一刹那间展现,这是怎样激动人心的时刻!恰如刚刚构思好一篇十分得意的文章,将要展纸挥笔的当口,也恰如自己崇拜的球员,在终场前得到一个绝佳的射门机会,即将起脚攻入致胜一球的那一刻,我有时有一种喘不过气来的感觉。
    ⑧我还有一个执拗的习惯 :好在贫瘠的荒凉的山间沙漠流连。岩间石缝中生长的斑痕累累千扭百弯的怪柏齐松,荒漠中的一株或一丛“沙打旺”或骆驼草,石板上的一片黄绿浅灰的苔藓,我都向他们注目。这些景象剥落了我热烈的情感,凸现出严峻的理性,它们并不可怜,我是敬仰它们!
    ⑨这是怎样坚忍不拔的生命追求!在极端恶劣的条件下,它们全都生长得很顽强,很自信,很精神!外在的温度、湿度、肥沃度等条件,对它们都不重要;它们几乎全靠自己内在的生命力。如果条件再恶劣一点,别的茂盛的生命可能化为死亡的尘埃,而它们却能依然故我,生机盎然;若果条件好一点,那它们该是一副怎样的葱茂!
    还有比生命现象更瑰丽更丰富的吗?
    ⑪有幸获得一次生命,就让生命严肃的展示吧。