Verb:
lengthen in time; cause to be or last longer;We prolonged our stay
She extended her visit by another day
The meeting was drawn out until midnight
lengthen or extend in duration or space;We sustained the diplomatic negotiations as long as possible
prolong the treatment of the patient
keep up the good work
v.动词
prolong, elongate, extend, lengthen, protract这组词都表示“延伸”。其区别是：
extend指直线状的伸展,引申指扩展势力、范围、影响等; lengthen指增加长度或延长时间; prolong指把时间过程延长到超过通常或正常的限度; elongate是技术用语,指空间尺度的延伸; protract指无限地、不必要地或令人厌烦地拖长。
delay，postpone，defer，suspend，prolong，put off这些动词或短语均有“推延，延期”之意。
delay普通用词，多指因外界原因推迟或耽误，也可指有意推迟。
postpone正式用词，语气较强，多指有安排的延期，常指明延期到一定的时间。
defer正式用词，语气强于postpone，多指故意拖延。
suspend指暂时中断以待某种条件的实现。
prolong指把时间延长至超过正常或通常的限度。
put off口语用词，与postpone同义，但较通俗。
prolong the period of validity延长有效期prolong life延年益寿
近义词 out出drag拖delay耽搁defer推迟extend延伸stretch伸展persist坚持amplify扩大sustain支持suspend暂停put off不安lengthen加长elongate延长protract延长draw out抽出drag out拖延postpone延期aggrandize增加keep up保持 继续 维持 跟上…spin out尽力维持一些日子, 拖长…反义词 shorten弄短
用作动词(v.
用作及物动词
S+ ～+n./pron.The book fair has been prolonged due to some reason.由于某种原因，书展被延长了。
The ceremony will be prolonged by ten minutes.仪式将延长10分钟。S+～+ v -ingTwo countries prolonged signing an agreement until details could be agreed on.两国推迟签约直到就细节达成协议。
动词98%,名词2%
用作及物动词How can we endeavor to prolong the brevity of human life?我们怎样才能延长短促的人生？
The meeting may beprolongedinto the evening because so many problems have to be solved tonight.会议可能要延长到夜里，因为今晚有太多问题要解决。
Low leakage current helps to prolong battery life.低漏电流有助于延长电池使用寿命。
Clear evidence of his intent is to prolong the ritual.显然他意在拖延典礼时间。
The defendant feigns illness to prolong the trial.为了拖延审判,被告装病。