词根词缀:extra-, extro-, extr-, exter-
【来源及含义】Latin: beyond, outside, on the outside, outward, external
【同源单词】Ab extra, ad extra, ad extremum, exteriorly, external, external reforming
词根词缀:famil-
【来源及含义】Latin: servant, domestic, part of a household ; members of a group; close relationships
【同源单词】blended family, extrafamilial, familial, familiar, familiarity, familiarize