N a ladder used to climb high walls, esp one used formerly to enter a besieged town, fortress, etc 云梯
这是攀墙用的梯子。
Here is an opening door, Wellcome you all who are getting down from the scaling ladder of real life.
这里，是一个打开的门，欢迎所有从生活云梯上下来的人。
The footmarks of pioneers are the starting point of historical progress and the shoulders of explorers are the ladder in scaling new heights in science.
开拓者的足迹是历史前进的起点。奋斗者的肩头是科学登高的阶梯。
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