睡神熊猫
阶梯:Ladder 名词 1.ladder 2.stairs flight 楼梯:Staircase 名词 1.stair 2.staircase 3.stairs 4.stairway Step 也可以做台阶的结实
李晓诗125
阶梯 ladder书是人类进步的阶梯Books are the ladders for us to climb high.stairs: n. 楼梯书是人类进步的阶梯Books are the mankind's progressive stairs.ladder: [ 'lædə ] n. 梯子