A set of keys是单数还是复数?

a set of keys 后用单数还是复数谓语 a set of keys作主语是谓语动词使用单数还是复数 a set of keys 后面的动词用什么形式啊?是单数还是复数啊?还有a pair of 什么的. a set of后面的名词是单数还是复数? 是a set of keys还是a set of key? 是there is a set of keys还是there are a set of keys? 英语短语开头要不要大写,要不要标点 如 是 a set of keys 还是 A set of keys. A set of keys谓语动词用单数吗? A set of keys a few of是单数还是复数 英语,“a set of+名词”后的谓语动词是单数还是根据后面的名词数否是复数而定? a set of keys please.