91. Arid regions in the southwestern United States have become increasingly inviting playgrounds for the growing number of recreation seekers who own vehicles such as motorcycles or powered trail bikes and indulge in hill-climbing contests or in caving new trails in the desert.

91.美國西部的不毛之地正成為玩耍的地方，對越來越多擁有摩托車或越野單車類車輛的，喜歡放縱于爬坡比賽或開辟新的沙漠通道的尋歡作樂者具有不斷增長的吸引力。

92. Stone does decay, and so tools of long ago have remained when even the bones of the man who made them have disappeared without trace.

92.石頭不會腐爛，所以以前的(石器)工具能保存下來，雖然它們的制造者已經(jīng)消失的無影無蹤。

93. Insects would make it impossible for us to live in the world; they would devour all our crops and kill our flocks and herds, if it were not for the protection we get from insect-eating animals.

93.昆蟲就將會使我們無法在這個世界上居住；如果我們沒有受到以昆蟲為食的動物的保護，昆蟲就會吞嚼掉我們所有的莊稼并殺死我們飼養(yǎng)的禽獸。 94. It is true that during their explorations they often faced difficulties and dangers of the most perilous nature, equipped in a manner which would make a modern climber shudder at the thought, but they did not go out of their way to court such excitement.

94.確實，他們在探險中遇到了極具威脅性的困難和危險，而他們的裝備會讓一個現(xiàn)代登山者想一想都會渾身顫栗。不過他們并不是刻意去追求刺激的。

95. There is only one difference between an old man and a young one: the young man has a glorious future before him and old one has a splendid future behind him: and maybe that is where the rub is.

95.老人和年輕人之間只有一個區(qū)別：年輕人的前面有輝煌的未來，老年人燦爛的未來卻已在它們身后。這也許就是困難之所在。

96. I find young people exciting. They have an air of freedom, and they have not a dreary commitment to mean ambitions or love comfort. They are not anxious social climbers, and they have no devotion to material things.

96.我們位年強人振奮。它們帶有自由的氣息，他們不會為狹隘的野心和貪婪享受而孜孜以求。他們不是焦慮的向上爬的人，他們不會對物質(zhì)性的東西難舍難分。

97. I am always amazed when I hear people saying that sport creates goodwill between the nations, and that if only the common peoples of the world could meet one another at football or cricket, they would have no inclination to meet on the battlefield.

97.每次我聽說體育運動能夠在國家間建立起友好感情，說世界各地的普通人只要能在足球場或板球場上相遇就會沒有興趣在戰(zhàn)場上相遇的話，我都倍感詫異。

98. It is impossible to say simply for the fun and exercise: as soon as the question of prestige arises, as soon as you feel that you and some larger unit will be disgraced if you lose, the most savage combative instincts are around.

98.沒有可能僅僅為了娛樂或鍛煉而運動：一旦有了問題，一旦你覺得你輸了你和你所屬團體會有失體面時，你最野蠻的好斗本能就會被激發(fā)出來。

99. It has been found that certain bats emit squeaks and by receiving the echoes, they can locate and steer clear of obstacles------or locate flying insects on which they feed. This echo-location in bats is often compared with radar, the principle of which is similar.

99.人們已經(jīng)發(fā)現(xiàn)，某些蝙蝠發(fā)出尖叫聲并靠接受回響來鎖定和避免障礙物——或者找到它們賴以為生的昆蟲。蝙蝠這種回響定位法常拿來和原理與之很相近似的雷達相比。

100. As the time and cost of making a clip drop to a few days and a few hundred dollars, engineers may soon be free to let their imaginations soar without being penalized by expensive failure.

100.隨著芯片制造時間和費用降低到了幾天和幾百美元，工程師們可能很快可以任他們的想象馳騁而不會被昂貴的失敗所懲罰。