n.绕绳下降；坐式下降法；v.用绳索下降； 变形： 复数：rappels过去式：rappelled过去分词：rappelled现在分词：rappelling第三人称单数：rappels 英英释义： rappel[ ræ'pel ]n.(mountaineering) a descent of a vertical cliff or wall made by using a doubled rope that is fixed to a higher point and wrapped around the