第17题: [单项选择]______ an answer, she decided to write him another letter. A. Not having received B. Not receiving C. Not received D. Not being received 参考答案:A 答案解析:[解析] 考查现在分词作状语的用法。现在分词可以作原因状语,等同于原因状语从句,本句中receive和主句主语she是主动关系,分词结构等于As she hadn't received an answ