Question

our products sell well, but ten years age , who could have imagined that they___such a big share in

our products sell well, but ten years age , who could have imagined that they___such a big share in the market
A were having B had had C were to have D had
the answer is C,tell me why

Answer 1

ten years ago, who could have imagined that they were to have such a big share in the market.

10年前有谁能想象得到它们（这些产品）会在市场上占到如此大的份额。

这里主要都是相当典型的“虚拟语气”的应用：
could have +动词过去分词
were + 动词不定式
这些都是在虚拟语气下的固定用法
请参阅下面链接复习一下就能明白其中的奥妙啦：

Answer 2

Our TV sets sell well, but ten years ago no one could have imaginedD吧应该是不能的因为在这里as不能代替that引导.. c D

Answer 3

C. were to have=would have,此处是一个虚拟语气，主句用了could have imagined,表示与过去的情况相反。“当时有谁能想到他们将能在市场上占有那么大的份额？”所以后半句应该有过去将来时。

Answer 4

选C. were to have=would have,考查虚拟语气，主句用了表示与过去的情况相反。从句应该用去将来时