all the required papers, he didn’t answer the questions fluently in class.
A. Having not read
B. Not having read
C. Not read
D. Not to read
网友回答
A. Having not read
(答案→)B. Not having read
C. Not read
D. Not to read
解析：考查非谓语动词做原因状语用法。He与read构成主动关系，根据句意可知是完成时且表示主动，所以使用现在分词形式。非谓语动词的否定式是在前面直接加not,所以选择B。结合句意可知B正确。句意：因为没有读完所有要求的论文，他在课堂上不能流利地回答问题。