task: implies usually a specific piece of work imposed by a person in authority or by circumstances: performed a variety of ~s for the company.


duty: implies an obligation to perform or a responsibility for performance: the ~ies of a lifeguard.


job: applies to a piece of work voluntarily performed or to an assigned bit of menial work and may sometimes suggest difficulty or importance: took on the ~ of turning the company around.


chore: implies a minor routine activity necessary for maintaning a household or farm and may stress the drabness of such activity: every child had a list of ~s to do.


stint: implies a carefully alloted or measured quantity of assigned work or service: during his ~ as a governor.


assignment: implies a definite limited task assigned by one in authority: your ~ did not include interfering with others.


task任务: 一件具体工作，duty职责: 义务责任，job工作: 卑微无偿或泛指，chore杂务家务: 琐碎常规无趣，stint任期: 慎重仔细指定的工作配额，assignment: 明确限定的任务


记忆方法: 1) 首字母组合成CAST演员和DJ音乐节目主持人<==两项任务             DJ是唱片或音乐节目主持人(全写为 disc jockey) CAST是电影全体演员  

         2) 任务的意思是一件要做的工作mean a piece of work to be done.首字母组合成CAST演员和DJ音乐节目主持人<==两项任务