题目

--Comeputers are so useful.They can do almost everything!--Yes.But they ___ what to do
--Comeputers are so useful.They can do almost everything!
--Yes.But they ___ what to do
A must be told
B has to be known
C．has to be known
D．will know

提问时间：2021-01-28

答案

A .. BC应该是have to 因为主语是they..而且be known 是被知道,应该是know.根据语境不应用将来时,所以不选D