问题补充:
His sister left home in 1998, and ever since.
A. has not heard from
B. had not heard from
C. has not been heard of
D. had not been heard of
答案:
A. has not heard from
B. had not heard from
(答案→)C. has not been heard of
D. had not been heard of
解析:句意:他的姐姐在1998年离开家,从那个时候起,再没有听说她。Hear from收到某人的来信,hear of听说,表示自过去某一时刻到说话时这段时间的经历,用现在完成时,选C。