Students in this school each ____ going to do voluntary work
Students in this school each ____ going to do voluntary work during the coming summer holiday. A.are B.is C.were D.was 该选择哪一个答案. 题意:在即将到来的暑假中这个学校的每个学生都将参加志愿活动.句子主语为students,each为同位语. 但我有点疑问each 不是代表单数意思的吗?如果students,each为同位语为什么不用all 来和students 做同位语呢?