stop: applies to action or progress or to what is operating or progressing and may imply suddenness or definiteness: ~ped the conversation.   (sudden突然表示没有预料到a sudden rain突然下雨)   (definite明确: 等于clear，不模棱两可it's too soon to give a definite answer现在给出明确答复还为时过早)


cease: applies to states, conditions, or existence and may imply gradualness and a degree of finality: by nightfall the fighting had ~d.    (final最终的,表示不会再延续或变化，如最终判决、终审final judgment，如the finality of death死亡的终极性，如final day末日，final单用表示决赛)    (state状态是condition状况的集合/总称)


quit: may stress either finality or abruptness in stopping or ceasing: the engine faltered, sputtered, then ~ altogether.  abrupt唐突就是sudden，强调没有预警简慢无礼，如an abrupt refusal唐突的拒绝           (falter停步不前说话犹豫，如 the economy is faltering经济止步不前)  （sputter发出劈啪声，停止2个意思，如the truck sputtered and stopped卡车噼啪响了几声停下了）


discontinue: applies to the stopping of an accustomed activity or practice: we have ~d the manufacture of that item.  (accustomed习惯性的惯用的suggests fixed habit or invariable custom固定的习惯习俗，如accepted the compliment with her accustomed modesty她以惯有的谦虚接受别人对她的赞美，=habitual )    （custom习俗: 人们长期遵守的习惯，几乎是不成文的法律，如customs and traditions varying greatly between provinces even cities不同省甚至市的传统习俗差异巨大，又如the custom of mourners wearing black at funerals追悼者葬礼穿黑色衣服的习俗）


desist: implies forbearance or restraint as a motive for stopping or ceasing: ~ed from further efforts to persuade them.


stop停止: 用于动作(action or progress)，表示突然而明确(不是半停未停)(没说final,可能重新开始)，cease也是停止: 用于状态，表示逐渐并最终停止，quit停止: 强调突然和最终，discontinue停止: 指停止惯有的的活动行为，desist停止: 指出于克制而停止


记忆方法: 1）首字母SCQDD想成冲动的事情<==应该停止          "停"的本义是"旅人在亭子边停留停驻"以休息，"止"的本意是"脚(趾)不再动"，停是持续性动作，持续一段时间，止是结束性动作

         2）停止的意思是中断活动mean to suspend or cause to suspend activity.   （suspend不定期中断暂停a stopping until some condition is satisfied，如all business has been suspended while repairs are being made维修时所有业务暂停）