a solemn promise 誓言 ■(vows)a set of such promises committing one to a prescribed role, calling, or course of action, typically to marriage or a monastic career (尤指为婚姻或僧侣生涯立下的)誓约
verb
[reporting verb]solemnly promise to do a specified thing 宣誓,立誓,发誓 [with clause]he vowed that his government would not tolerate a repeat of the disorder. 他郑重宣告他的政府绝对不能容许再次发生混乱。 [with direct speech]one fan vowed, ‘I'll picket every home game’. 一个球迷发誓说:“我一定为每一次主场比赛放哨”。
[with obj.](archaic)dedicate to someone or something, especially a deity (古)(尤指对神)立誓奉献 I vowed myself to this enterprise. 我立誓终身为这事业服务。
语源
Middle English: from Old French vou, from Latin votum (see vote); the verb from Old French vouer