1. Typical of the grassland dwellers of the continent is the American antelope, or pronghorn.

　　1.美洲羚羊，或稱叉角羚，是該大陸典型的草原動物。

　　2. Of the millions who saw Haley's comet in 1986, how many people will live long enough to see it return in the twenty-first century.

　　2. 1986年看見哈雷慧星的千百萬人當(dāng)中，有多少人能夠長壽到足以目睹它在二十一世紀(jì)的回歸呢？

　　3. Anthropologists have discovered that fear, happiness, sadness, and surprise are universally reflected in facial expressions.

　　3.人類學(xué)家們已經(jīng)發(fā)現(xiàn)，恐懼，快樂，悲傷和驚奇都會行之于色，這在全人類是共通的。

　　4. Because of its irritating effect on humans, the use of phenol as a general antiseptic has been largely discontinued.

　　4.由于苯酚對人體帶有刺激性作用，它基本上已不再被當(dāng)作常用的防腐劑了。

　　5. In group to remain in existence, a profit-making organization must, in the long run, produce something consumers consider useful or desirable.

　　5.任何盈利組織若要生存，最終都必須生產(chǎn)出消費者可用或需要的產(chǎn)品。

　　6. The greater the population there is in a locality, the greater the need there is for water, transportation, and disposal of refuse.

　　6.一個地方的人口越多，其對水，交通和垃圾處理的需求就會越大。

　　7. It is more difficult to write simply, directly, and effectively than to employ flowery but vague expressions that only obscure one's meaning.

　　7.簡明，直接，有力的寫作難于花哨，含混而意義模糊的表達(dá)。

　　8. With modern offices becoming more mechanized, designers are attempting to personalize them with warmer, less severe interiors.

　　8.隨著現(xiàn)代辦公室的日益自動化，設(shè)計師們正試圖利用較為溫暖而不太嚴(yán)肅的內(nèi)部裝飾來使其具有親切感。

　　9. The difference between libel and slander is that libel is printed while slander is spoken.

　　9.誹謗和流言的區(qū)別在于前者是書面的，而后者是口頭的。

　　10. The knee is the joints where the thigh bone meets the large bone of the lower leg.

　　10.膝蓋是大腿骨和小腿脛的連接處。

　　11. Acids are chemical compounds that, in water solution, have a sharp taste, a corrosive action on metals, and the ability to turn certain blue vegetable dyes red. 11.酸是一種化合物，它在溶于水時具有強烈的氣味和對金屬的腐蝕性，并且能夠使某些藍(lán)色植物染料變紅。

　　12. Billie Holiday's reputation as a great jazz-blues singer rests on her ability to give emotional depth to her songs.

　　12. Billie Holiday's作為一個爵士布魯斯樂杰出歌手的名聲建立在能夠賦予歌曲感情深度的能力。

　　13. Essentially, a theory is an abstract, symbolic representation of what is conceived to be reality.

　　13.理論在本質(zhì)上是對認(rèn)識了的現(xiàn)實的一種抽象和符號化的表達(dá)。

　　14. Long before children are able to speak or understand a language, they communicate through facial expressions and by making noises.

　　14.兒童在能說或能聽懂語言之前，很久就會通過面部表情和靠發(fā)出噪聲來與人交流了。

　　15. Thanks to modern irrigation, crops now grow abundantly in areas where once nothing but cacti and sagebrush could live.

　　15.受當(dāng)代灌溉(技術(shù)設(shè)施)之賜，農(nóng)作物在原來只有仙人掌和蕎屬科植物才能生存的地方旺盛的生長。

　　16. The development of mechanical timepieces spurred the search for more accurate sundials with which to regulate them.

　　16.機械計時器的發(fā)展促使人們尋求更精確的日晷，以便校準(zhǔn)機械計時器。

　　17. Anthropology is a science in that anthropologists use a rigorous set of methods and techniques to document observations that can be checked by others.

　　17.人類學(xué)是一門科學(xué)，因為人類學(xué)家采用一整套強有力的方法和技術(shù)來記錄觀測結(jié)果，而這樣記錄下來的觀測結(jié)果是供他人核查的。

　　18. Fungi are important in the process of decay, which returns ingredients to the soil, enhances soil fertility, and decomposes animal debris.

　　18.真菌在腐化過程中十分重要，而腐化過程將化學(xué)物質(zhì)回饋于土壤，提高其肥力，并分解動物糞便。

　　19. When it is struck, a tuning fork produces an almost pure tone, retaining its pitch over a long period of time.

　　19.音叉被敲擊時，產(chǎn)生幾乎純質(zhì)的音調(diào)，其音量經(jīng)久不衰。

　　20. Although pecans are most plentiful in the southeastern part of the United States, they are found as far north as Ohio and Illinois.

　　20.雖然美洲山河桃樹最集中于美國的東南部但是在北至俄亥俄州及伊利諾州也能看見它們。