英语选择题Ithinkatleastoneofthestudentsthissongbefore.A.havelearnedB.mustlearnC.haslearnedD.hadleaned为什么选c啊就是用单数?是有关主谓一致的内容

Question

英语选择题
I think at least one of the students ____ this song before.
A. have learned B. must learn
C. has learned D. had leaned
为什么选c啊 就是用单数? 是有关主谓一致的内容

Answer 1

I think at least one of the students ____ this song before.
A.have learned B.must learn
C.has learned D.had leaned
答：本题答案为 C
因为 at least one 后面应该+单数,记得有个系统错误提示是,at least one service or driver failed during system .
many a ...或more than one...,谓语动词采用单数形式．
rain and fog的话,应该就是并列结构作主语时谓语用复数,后面用are.
如果前面有冠词就要注意：当主语由and连结时,如果它表示一个单一的概念,即指同一人或同一物时,谓语动词用单数,and 此时连接的两个词前只有一个冠词.