His sister left home in 1998, and_________ since.
A.had not been heard of
B.has not been heard of
C.had not heard of
D.has not heard of
正确答案:B
His sister left home in 1998, and_________ since.
A.had not been heard of
B.has not been heard of
C.had not heard of
D.has not heard of
正确答案:B