Either the teacher or the students________able to give the answer．
A.is
B.are
C.isn't
D.aren't
网友回答
B解析分析：主语是Either the teacher or the students，由either A or B作主语时，主谓一致的关系是看B，B是单数的话就作为单数，B是复数的话就作为复数，此处应该从are或aren't来决定。either A or B可以在not之后，不能在not之前。所以选B项are．(延伸)both A and B总是复数，neither A nor B，either A or B，not only A but also B总是看后面的，即看B，如：Not only the teacher but also the students are able to give the answer．Not only his classmates but also Tom is able to give the answer．