betroth
/bɪˈtrəuð; bɪ`troð/ v[usu passive 通常用於被动语态
Tn, Tn.pr]
~ sb (to sb) (arch or fml 古或文) bind sb with a promise to marry; engage sb to marry 将某人许配给; 订婚
She was betrothed (to the duke). 她已许配（给公爵）了.
The pair were later betrothed. 那对男女後来订婚了.