By no means promised to keep you of how their business was going on.
A. he has；informing
B. he has；informed
C. has he；informing
D. has he；informed
网友回答
A. he has；informing
B. he has；informed
C. has he；informing
(答案→)D. has he；informed
解析：考查倒装句与分词短语。By no means绝不，是一个否定词，放在句首，后面使用部分倒装句。第一空排除AB；you与inform构成被动关系，所以使用过去分词表示被动。答案为D。