答案网Some animals pant and sweat to speed evaporation of body moisture and thus cool themselves.答案及解析。
答案网One of the greatest breakthroughs for professional women came in 1973 when the field of banking o
答案网The first important exposition in the United States was held in Philadelphia in 1876. 答案及解析。
答案网The Salk vaccine is a major factor in the fight to eradicate polio.答案及解析。
答案网Double Eagle in the first transatlantic balloon, was greeted by avid crowds in France. 答案及解析。
答案网Solid geometry has enabled astronomers to calculate the positions of the heavenly bodies relative
答案网Some children display an unquenchable 难以抑制的 curiosity about every new thing they encounter.答案及解析。
答案网Cream of tartar 酒石 , a weak acid, can be added to egg whites to help them foam泡沫 when they are be
答案网An oversight 遗漏 (miss, overslaugh) in proofreading often results in printed errors.答案及解析。
答案网Comets are still regarded with awe by some people. 答案及解析。
答案网The flower bud of a water lily 百合 opens at sunset since .its opening is triggered(commence) .by t
答案网With lasers scientists can probe many physical processes, such as combustion, once beyond our ken
答案网The economy of Dallas, Texas, is strong and diversified . 答案及解析。
答案网The Native American interpreter Sacajawea was a valuable member of the Lewis and dark expedition
答案网The fear of smallpox, which terrorized the eighteenth century, has no analogy(likeness) today. 答案
答案网Food must be moist in order to have a taste. 答案及解析。
答案网People who do not sleep enough tend to become irritable . 答案及解析。
答案网Although the Carbon 14 method of dating old objects is not foolproof , it is the best method avai
答案网 All living organisms, regardless of their unique identity, have certain biological, chemical, an
答案网How many people are aware that a dancer with the New York City Ballet typically wears out a minim