on ten years of observation and study,Professor Wang announced that everyone dre
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_____on ten years of observation and study,Professor Wang announced that everyone dreams every night, whether they realize it or not.
A.Basing B.Based C.Been based D.Having based
试题答案
B
解析： 句意是“基于十年的观察和研究,王教授声称,每个人每晚都在做梦,不管他们是否意识到。此句中如果选A,则理解为是Basing与主语Professor Wang是主动关系,这时Basing后面应该有宾语。本题空格后没有宾语,我们就该用Based过去分词形式作状语,与后面的说法是被动关系。