A set of keys __ (be) on the floor.怎么填?
问题描述：
A set of keys __ (be) on the floor.怎么填?
答
A set of keys is on the floor
a set of keys"指一套钥匙，表单数概念,所以后边的动词用单数.
答
is 因为A set of keys指一串钥匙 用单数
答
is.一串是单数
答
is
set 是一套的意思
就像a pair of shoes
答
应该填 is
a set of 的意思是"一套,一组"
所以后面接的名词一定是复数
而对于它的谓语,因为是 a set 一套,所以用单数is
如果是two sets of ,那么谓语就应该用are