核心问题
each of + 复数名词作主语时, 其谓语动词是用单数, 还是用复数?
词典解答
所有的英语语法书都指出，在 each of + 复数名词作主语时，其谓语动词应当用单数：Each of them has signed the petition. (CGEL) 他们每个人都在请愿书上签了名。
但是,我们在 LDCE 上发现了一个反例:
Each of the 2 beautiful girls upstairs is/are married. (LDCE, p. 345) 楼上那两个漂亮的女孩都已结了婚。
考生注意:各类标准英语考试要求 each of Ns 的谓语动词使用单数:
It may be said that in some countries each of the citizens help to decide the government A B C D
policy. (TOEFL)