____of them have known about the plan because it has been kept a secret.
问题描述：
____of them have known about the plan because it has been kept a secret.
A.Either
B.Neither
C.No one
D.None
答
选B. either指两者之中的任意一个不...,看到原句中的have known,可知主语是复数,而符合题意的就B, neither, 指两者都不.为什么none不对啊~none指没有一个人..如果是none，主语就是单数了。