In the past few years a great many teachers have found very important to teach their stud

问题补充：

In the past few years, a great many teachers have found very important to teach their students how to learn.

A. this

B. that

C. one

D. it

答案：

A. this

B. that

C. one

(答案→)D. it

解析：考查形式宾语。在英语中只有it可以作为形式主语，形式宾语。在本句中It作为形式宾语，代替真正的宾语to teach their students how to learn.句意：在过去的几年里，很多老师都发现教会学生如果学习很重要。故D正确。