后楼梯

例句：

1. 1. The stairs are steep, so I need to take extra care.
   楼梯很陡峭，所以我需要小心。
2. 2. The old lady has a hard time climbing the stairs.
   那位老太太爬楼梯很困难。
3. 3. We went up the stairs and found the door at the top.
   我们爬上楼梯，找到了门在顶部。