Lucy 和 Lily 的妈妈 （ 分别所有 ）的英语Lucy’s and Lily’s mother’s
Lucy和Lily的妈妈指共同的妈妈时 是 Lucy and Lily's mother指各自的妈妈时是Lucy's and Lily's mothers如Lucy and Lily's mother is a doctor.Lucy's and Lily's mothers are doctors
