31.  Although apparently rigid, bones exhibit a degree of elasticity that enables the skeleton to withstand considerable impact.

32.  That xenon could not form chemical compounds was once believed by scientists.

33.  Research into the dynamics of storms is directed toward improving the ability to predict these events and thus to minimize damage and avoid loss of life.

34.  The elimination of inflation would ensure that the amount of money used in repaying a loan would have the same value as the amount of money borrowed.

35.  Futurism, an early twentieth-century movement in art, rejected all traditions and attempted to glorify contemporary life by emphasizing the machine and motion.

36.  One of the wildest and most inaccessible parts of the United States is the Everglades where wild life is abundant and largely protected.

37.  Lucretia Mott’s influence was so significant that she has been credited by some authorities as the originator of feminism in the United States.

38.  The activities of the international marketing researcher are frequently much broader than those of the domestic marketer.

39.  The continental divide refers to an imaginary line in the North American Rockies that divides the waters flowing into the Atlantic Ocean from those flowing into the Pacific.

40.  Studies of the gravity field of the Earth indicate that its crust and mantle yield when unusual weight is placed on them.

41.  The annual worth of Utah’s manufacturing is greater than that of its mining and farming combined.

42.  墙花（wallflower）之所以叫墙花，是因为其脆弱的枝干经常要靠墙壁或顺石崖（stony cliffs）生长，以便有所依附。

43.  社会心理学的主要焦点是人与人之间的交往，而不是他们各自生活中的事件。

44.  给美国的新移民增加教育设施比任何社会运动都更多的激发了Elizabeth Williams的热情。

45.  典型的鹌鹑都长有短而圆的翅膀，凭此他们可以在受惊时一跃而起，飞离它们的躲藏地。

46.  根据人类学家的说法，直立行走的人的鼻祖面部轮廓与黑猩猩相似，额头后倾，眉毛突出。

47.  直到1866年第一条横跨大西洋的电缆才完全成功的架通。

48.  John Crowe Ransom在他的著作中描述了他认为是由科学技术给社会带来的精神贫困。

49.  父母的教导如果坚定，始终如一和理性，孩子就有可能充满自信。

50.  北美远古的Hopewell人很可能种植了玉米和其他农作物，但打猎和采集对他们的经济贸易仍是至关重要的。

51.  使用多种多样的符号可以在一张地图里放进大量的信息。

52.  无政府主义这个词描述的是一堆理论和态度，它们的主要共同点在于相信政府是有害的，没有必要的。

53.  恐怕没有谁对大多数美国人的日常生活影响能超过汽车生产的先驱亨利.福特。

54.  使用精心挑选的无意义词汇，可以检验语言学科里许多基本的假定。

55.  优化历史是由一连串的迷人事件组成，其源头大概可以上溯到最早的图画。

56.  相互般配的珍珠，串成一条项链，就能卖到比单独售出好得多的价钱。

57.  十八世纪时，“小乌龟”是迈阿密部落的酋长，该部落的地盘就是今天的印第安那州和俄亥俄州。

58.  在竹子的近七百个品种中，有的全长成还不到一英尺，有的却能在二十四小时内长出三英尺。