The student said there were a few points in the essay he impossible to understand.A. had

问题补充：

The student said there were a few points in the essay he impossible to understand.

A. had found

B. finds

C. has found

D. would find

答案：

(答案→)A. had found

B. finds

C. has found

D. would find

解析：句意，学生说他发现这篇文章里有几点很难理解。通过分析句子结构，可知这个句子中包含一个宾语从句。主句用的是一般过去时，从句要用相应的过去时态，所以这里用过去完成时。