703] So far
nothing _____ Tom. I want to know the reason _______ he hasn’t written to me.
[译文] 到目前为止,还没有收到汤姆的任何来信。我想知道他没给我写信的原因。
A. heard from; why
B. has been heard from; why
C. was heard from; that
D. has heard from; that
[答案及简析]
B。 含有so far的句子应该时现在完成时态;reason作先行词,定与从句应该用that引导。