49. Children with parents whose guidance is firm, consistent, and rational are inclined to possess high levels of self-confidence.
    父母的教導(dǎo)如果堅(jiān)定，始終如一和理性，孩子就有可能充滿自信。

50. The ancient Hopewell people of North America probably cultivated corn and other crops, but hunting and gathering were still of critical importance in their economy.
    北美遠(yuǎn)古的Hopewell人很可能種植了玉米和其他農(nóng)作物，但打獵和采集對(duì)他們的經(jīng)濟(jì)貿(mào)易仍是至關(guān)重要的。

51. Using many symbols makes it possible to put a large amount of inFORMation on a single map.
    使用多種多樣的符號(hào)可以在一張地圖里放進(jìn)大量的信息。
　　
52. Anarchism is a term describing a cluster of doctrines and attitudes whose principal uniting feature is the belief that government is both harmful and unnecessary.
    無go-vern-ment主義這個(gè)詞描述的是一堆理論和態(tài)度，它們的主要共同點(diǎn)在于相信go-vern-ment是有害的，沒有必要的。
　　
53. Probably no man had more effect on the daily lives of most people in the Untied States than did Henry Ford a pioneer in automobile production.
    恐怕沒有誰對(duì)大多數(shù)美國(guó)人的日常生活影響能超過汽車生產(chǎn)的先驅(qū)亨利.福特。
　　
54. The use of well-chosen nonsense words makes possible the testing of many basic hypotheses in the field of language learning.
    使用精心挑選的無意義詞匯，可以檢驗(yàn)語言學(xué)科里許多基本的假定。
　　
55. The history of painting is a fascinating chain of events that probably began with the very first pictures ever made.
    優(yōu)化歷史是由一連串的迷人事件組成，其源頭大概可以上溯到最早的圖畫。
　　
56. Perfectly matched pearls, strung into a necklace, bring a far higher price than the same pearls told individually.
    相互般配的珍珠，串成一條項(xiàng)鏈，就能賣到比單獨(dú)售出好得多的價(jià)錢。