双写：hit,cut,get,sit,put,shut,fit,spit吐痰,set设置,forget,babysit,shop,stop,drop,hiccup打嗝,trip绊倒,slip滑倒,step踩,nap 打盹,mop 拖洗,抹,run,win,begin,plan,dig,swim,nod点头,rob抢劫
去e：have,file,bite,take,cave,dive,save……