Having cut off the electricity,the workers began to repair the machine which didn't work这里Having cut off the electricity是非谓语动词做什么成分呢?为什么要用完成时态呢?

CUT OFF THE MEAT是什么意思 cut off the traffic是什么意思 Having cut off the electricity,the workers began to repair the machine which didn't work这里Having cut off the electricity是非谓语动词做什么成分呢?为什么要用完成时态呢? the doctor insisted on one of the patient's legsthe doctor insisted on one of the patient's legs____a.being cut offb.to be cut offc,having cut offdto have cut off 翻译im not having it all cut off. i'm not having all of my hair cut off Cut off the scales and cut open the stomach cut-off cut-off With the electricity ,all the machines stoppedA .was cut off B cut off [W29] _______ by the terrible earthquake, Chile's second largest city, the southern town ofConcepcion, was ________ from the outside.A.Having struck ;cup up B.Struck ; cut downC.Having struck ;cut out D.Struck ;cut off 翻译包括选项,并分析. .___by the heavy snowfalls,Chenzhoum a city in South China,was cut off from the outside,___water and electricity shortage.A.Having struck;facing B.Having struck;facedC.struck;facing D.Struck;faced我想知道为什么? The yellow river _______ several valleys A.cut off B.cut through C.cut down D.cut across some people( )the trees in the forest A.cut down B.cut off我觉得是cut down但是答案上是cut off 6.When the city was ___ ,everyone knew that total defeat was certain .A cut off B cut down C cut across D cut out 7.If we ___ everything ready by now ,we should be having a terrible time tomorrow .A hadn’t got B didn’t get C wouldn’t have got D cut off 什么意思 cut off的过去式 cut off的意思