She is said in the United States for four years before she came back to work in our pany.
A. to study
B. to be studying
C. to have studied
D. studying
网友回答
A. to study
B. to be studying
(答案→)C. to have studied
D. studying
解析：常用句型 sth/sb is said to do ....据说。。。题中出现了for four years 说明要用完成时。