occurrence: implies any happening without intent, volition, or plan: a meeting that was a chance ~.    （volition意志力决心，是"使用个人意志决心的能力the faculty or power of using one's will"，使用时可以和will互换）    occur动词发生，也是泛指使人看见注意stresses presentation to sight or attention没有目的决心计划，如such events, when they occur, fascinate the public这种事情发生时，令公众心驰神往


event: usually implies an occurrence of some importance and frequently one having evident antecedent causes: the sequence of ~s following the assassination.    （cause原因，因果中的因，是reason的基础词因此更通用，如the cause of the train wreck火车失事的原因）


incident: suggests an occurrence of brief duration or relatively slight importance: one of the minor ~s of the war.   （incident解释为an event or happening，如an amusing incident一件趣事，如he came to regret the whole incident他开始对整件事情感到后悔，如Lugou Bridge/Xi'an Incident七七卢沟桥/西安事变，a border/diplomatic/terrorist incident边境/外交冲突/恐怖事件，可见incident可能不重要也可能重要，只是不重要的时候更多）  固定搭配without incident平安无事，如he arrived home without incident平安无事到家


episode: stresses the distinctiveness or apartness of an incident: recounted some amusing ~s from his youth.    （1、电视剧里的一集，如don’t miss next week’s exciting episode别错过下周激动人心的下一集，如the final episode will be shown next Sunday下周日将播出最后一集    2、片断a short, distinctive, apart period of time，如one of the funniest episodes in the book occurs in Chapter 6书中最有趣的片段之一在第6章）


circumstance: implies a specific detail attending an action or event: couldn't remember the exact ~s.    (specific=detailed具体即详细,definite=clear明确即清晰)   (definite就是clear, 就像specific就是detailed，请死记)


occurrence发生的事情: 泛指任何无目的决心计划（地发生）的事情，event事件: 有明显起因的重要事情，incident事情: 表示时间短不重要的事情，episode事情一集: 强调事情独特孤立，circumstance情况: 指具体细节


记忆方法: 1）首字母OEIEC想成奥委会IOC和眼保健操EE<==事件         "事情"指人类生活中的一切活动和所遇到的一切现象，如《礼记·大学》："物有本末，事有终始"，"事件"和事情同义，还表示事项，此条取名事件，只是更书面化些

         2）事件的意思是发生的现象活动mean something that happens or takes place.     happen发生的意思是come about出现