seasonable: implies appropriateness to the season or being perfectly fitted to the occasion or situation: ~ weather.   （appropriate十分合适=fit）  （又如seasonable temperatures/clothes/moment合时令的气温/衣服/适当的时机）   （season季节；occasion时间时机time or situation；situation情况，"合适的"情况即时机，三个词可统一译为"时间"）

timely: applies to what occurs or appears at the time or moment when it is most useful or valuable: a ~ warning.   （又如timely arrival/reminder/rain/snow及时赶到/提醒/雨/瑞雪）


well-timed: applies to what is so timely as to suggest care, forethought, or design: a ~ remark that stifled objections.   （如he built the company through a string of well-timed acquisitions通过一系列时机恰到好处的并购，他建立了这家公司，如本例恰到时机的一句话）


opportune: describes something that comes, often by chance, at the best possible moment and works to the advantage of those concerned: an idea that arose from an ~ remark.   （又如he couldn't have arrived at a less opportune moment他当时来得太不是时候了，如the opportune use of humour to lower tension适时运用幽默来缓和紧张气氛） 这个词的名词是机会机遇


pat: may apply to what is notably apt, ready, or well-suited to the occasion: a ~ remark; or to what is so very apt as to be suspect: offered an alibi that seemed too ~.   apt贴切，即语言精确得体，如a speech laced with some apt quotations演讲中包含了贴切的引用


seasonable合时令: 指某物适合于时间，timely及时适时: 表示某物在最有用的时间发生，well-timed时间恰好: 像是事先精心设计的，opportune时间恰好: 在最有利的时间发生，pat时间恰好: 明显恰到好处，甚至让人怀疑


记忆方法: 1) 首字母STWOP想成W我 + STOP停止<==适时停止

         2) 适时的意思是适合于时间mean peculiarly appropriate to the time or situation.首字母STWOP想成W我 + STOP停止<==适时停止