TT-GWD 2-34 中动词ing形式做插入语的逻辑主语问题

ypoint

请教一下，如下题，正确答案是C。presuming...在里面做插入语。问题是动词ing形式在句子里不是表伴随动作或伴随结果么？下面句子里面没有逻辑主语啊？请教如何理解？感谢感谢。


NASA’s methodical approach to the exploration of Mars has not yet answered the questions of whether biological life forms ever emerged on Mars and whether, presuming such life forms having left fossil traces to begin with, those traces can still exist in some moist recesses of the cold and arid planet.


A. and whether, presuming such life forms having left fossil traces to begin with, those traces can
B. and whether, if it is presumed that such life forms left some fossil traces to begin with, can those traces
C. and whether, presuming such life forms left fossil traces to begin with, those traces
D. and, presuming such life forms did leave some fossil traces to begin with, if they can
E. and, presuming such life forms to have left fossil traces to begin with, if they

ypoint

自己顶，继续求教。

mongmong

我也不懂哎~~~

aeoluseros

presuming, considering这种其实都已经约定俗成成了连词或介词。。而不再是现在分词。所以就不需要逻辑主语了。

mongmong

presuming, considering这种其实都已经约定俗成成了连词或介词。。而不再是现在分词。所以就不需要逻辑主语了。

-- by 会员 aeoluseros (2011/11/4 18:50:57)

多谢！

eleven8310

也在纠结这个，做题的时候选错了。这个解释很好，谢谢。