family表示家人的时候,它是属于单数形式还是属于复数形式?

family
英 ['fæmɪlɪ; -m(ə)l-] 美 ['fæməli]
n.家庭；家族；家属；子女；亲属；僚属
adj.家庭的,家族的
[ 复数 families ]
Of what family is he from?
他出身于什么样的家庭?
《新英汉大辞典》
They cabled the news to her family.
他们把这个消息电告她的家属.
《21世纪大英汉词典》
She talked at us about her family life.
她对我们滔滔不绝地讲她的家庭生活
families
英 美 ['fæməli]
n.家庭（family的复数）；家族
Many families were drowned out by the recent flood.
许多家人被最近这次洪水搞得无家可归.
《21世纪大英汉词典》
The hatred between these two families never quite flickered out.
这两家人之间的仇恨从来没真正消除.
《21世纪大英汉词典》
The young couple was betrothed with the approval of both families.
这对年轻的情侣在双方家庭的同意下订了婚.