U C 义务，责任a condition or influence that makes it necessary for sb to do sth; a duty

　acknowledge ～s　表示感谢
　fulfil〔meet, perform〕 an ～　履行义务
　lay〔place〕 an ～ on sb　使…承担义务
　repay an ～　报恩
　undertake an ～　承担义务
　legal〔moral〕 ～　法律〔道德〕上的义务
　mutual ～　相互的义务
　social ～　社会义务
　international ～　国际义务
　solemn ～　庄严义务
　written ～s　书面契约
　citizenship ～s　公民义务
　family ～s　家庭义务
　free sb from an ～　解除某人的义务
　lay sb under an ～　施恩于某人
　the ～ of citizens　公民的义务

　A good citizen has certain obligation to society.　一个好公民对社会有某些义务。
　His social obligation compels him to make a round of visits.　他的社会职责使得他不得不进行一系列访问。

 ♣ under an obligation
　有义务　being compelled by law, etc.
　She is under an obligation to her adoptive mother.　她有义务赡养她的养母。
　Every player is under an obligation to keep the rules.　每个选手都必须遵守这些规则。
　The court laid the young thief under an obligation to report to the police station once a week.　法院强迫那个小偷每周向警察局报到一次。
　Their frequent invitation places us under an obligation to invite them to our house for a change.　他们经常邀请我们，我们只好礼尚往来邀请他们到我们家。
 ♣ under no obligation
　没有义务　not being compelled by law, etc.
　I'm under no obligation to do it.　我没有义务去做那件事。

 ♣ obligation, duty
　参见duty条。
 ♣ obligation, responsibility
　obligation　仅指对他人应尽的职责和义务，没有对自己应尽的责任的含意；responsibility则指一个人必须对后果负责的职责或义务。

　［同义词］ charge, duty
　［反义词］ choice, freedom
　［词源］拉丁语obligatio（使受约束而做事）