When and where to go for the on-salary holiday___yet.A.are not knownB.have not been knownC.is not being knownD.has not b
问题描述：
When and where to go for the on-salary holiday___yet.A.are not knownB.have not been knownC.is not being knownD.has not been known答案是C每一个选项都讲一下谢谢!
答
答案：D
when and where to go for the on-salary holidy 短语做这个句子的主语,谓语动词用单数,yet决定这个句子的时态为现在完成时.