问题
选择题
_______ that he made an obvious mistake, Jeff went on with his speech.
A．Not realized
B．Not to realize
C．Not to have realized
D．Not realizing
答案
答案：D
题目分析：考查非谓语动词。主语Jeff与realize之间够成逻辑上的主动关系，所以用现在分词。根据句意应为否定形式所以要在分词前加not.句意： Jeff 没有意识到自己犯了一个明显的错误，所以继续他的演讲。