Before it was proven that the earth was round, it was a well-known “fact” that it was flat.This “fact” was so widely accepted that no one dared test it, because they thought if they did sail out beyond the horizon they would fall off the edge.__16_ _
The “fact” remained undoubted until Columbus questioned common knowledge and asked “what if？” __17_ _
In spite of our tendency to think of reality as the fixed basis of our experience, the definition of reality changes every time someone pushes the boundary of traditional wisdom.__
“The reasonable man adapts himself to the world，” wrote Bernard Shaw, “the unreasonable one persists in trying to adapt the world to himself.” __
Open your mind to the possibility that the world is made up of a countless experiences from the very worst to the very best.__
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G
考查学生对语意承接的把握。“这个事实得到了广泛的认同，以至于没人敢去验证它是否正确。因为大家担心如果航行的船只一跨过地平线，就会从边界上掉下去。换句话说，因为大家都相信这件事情不能做，于是就没有人去做。”
此题是过渡型句子题。所以选择选项G。
对于文章结构不敏感。
D
考查学生对语意承接及上下文指代的把握。D选项中的This question指代的即上文所提到的“what if？” “这种状况一直延续到哥伦布质疑这个常识的那一刻——‘如果不是……会怎样？’这个疑问彻底拓宽了他祖国的疆域，改写了历史，并且永久性地改变了人们所接受的现实。”
此题是过渡型句子题。所以选择选项D。
对于文章结构不敏感。
E
考查学生对上下文衔接句的把握。本句很好地衔接了下文的举例。
此题是过渡型句子题。所以选择选项E。
对于文章结构不敏感。
C
考查语意承接。
此题是过渡型句子题。所以选择选项C。
对于文章结构不敏感。
B
考查语意承接。
此题是过渡型句子题。所以选择选项B。
对于文章结构不敏感。