分享一则成语故事：
AmongtheoutstandingfiguresofChinesehistory, famouseitherfortheirintelligenceortreachery, CaoCaoisoneoftheforemost.
在中国历史上有许多人物以聪明狡诈而闻名，曹操就是其中之一。
Onesummer, CaoCaowasleadinghistroopsinapunitiveexpeditionagainstZhangXiu. Itwasextraordinarilyhot. Theburningsunwaslikeafire, andtheskywascloudless. Thesoldierswerewalkingonthewindingmountainpaths. Thedenseforestandthehotrocksexposedtothesunonbothsidesofthepathsmadethesoldiersfeelsuffocated. Bynoontimethesoldiers' clotheswerewetthroughwithsweat, andthemarchingspeedsloweddown. Somesoldersofweakphysiqueevenfaintedontheroadside.
有一年夏天，曹操率领部队去讨伐张绣，天气热得出奇，骄阳似火，天上一丝云彩也没有，部队在弯弯曲曲的山道上行走，两边密密的树木和被阳光晒得滚烫的山石，让人透不过气来。到了中午时分，士兵的衣服都湿透了，行军的速度也慢下来，有几个体弱的士兵竟晕倒在路边。
Seeingthatthemarchingspeedwasslowerandslower, CaoCaowasveryworriedbecausehefearedthathemightbunglethechanceofwinningthebattle. Buthowcouldtheyquickentheirspeed? CaoCaoatoncecalldetheguideandaskedhimonthequietwhethertherewasasourceofwaternearby.