两串钥匙是two set of keys还是two sets of keys

两串钥匙是two set of keys还是two sets of keys 两串钥匙是two set of keys还是two sets of keys,哪个对?为什么? I have two __ .A.set of keys B.set of key C.sets of keys D.s 是Some set of keys.还是Some sets of keys.(⊙o⊙)? I lost two ____(set)of keys 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? a set of keys ,a set of ...意为“一串···”,那么两串钥匙怎么表示_____________ 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. 我的那串钥匙是旧的.My set of keys 后的be 动词时用is 还是are. a set of keys please.