用适当形式填空:So far no letter ____(receive)from my friends

问题描述:

用适当形式填空:So far no letter ____(receive)from my friends

has been received
so far 是现在完成时的时间标志
而,letter 与receive 之间是被动的关系,letter是无法发出receive这个动作的,只有人可以.