But Bill Cuddington, caving in the eastern U.S.,worked out a simple way:rappelling down and climbing up a single rope tied to a rock.
请问下，这句rappelling down and climbing up a single rope tied to a rock. 的结构应该如何拆分理解？是a single rope之前省略了什么吗？with？如果没有省略感觉像是动名词直接作用于后面的绳子。但是机翻又是“用一根绑在岩石上的绳子下降并爬上”。谢谢解答。