有点小疑惑------many times,he still could-----many times,he still could not understand it.A Having been told B He had been toldCThough he had been told（Though he was told）DHaving told知道B,D不对,但为什么不选C?
问题描述：
有点小疑惑------many times,he still could
-----many times,he still could not understand it.
A Having been told
B He had been told
CThough he had been told（Though he was told）
DHaving told
知道B,D不对,但为什么不选C?
答
这是独立主格的Ving形式，这里牵扯到时态，C选项，过去完成时，过去式都是不准确的，假设用过去式的话，那后面主句应该是He still didn't understand it.
现在完成时表示从过去某一点到现在是个区间，这样的话就容易理解了，虽然被告知多次，但是还是不懂。
过去式是过去的某个点。
答
这里考察三点,
被动语态用法
状语从句用法
代词做主语时的用法：因为主语he在后半段已经使用,在前半句做状语从句时主语即后半段的he,C中主语重复出现,所以错误