"Watch your step on the stairs" is a commonly used phrase to warn people to be careful when cpmbing or descending stairs, as there is a risk of tripping or falpng.
This phrase originates from a safety concern for individuals on stairs, where it is important to pay attention to each step taken to avoid accidents.
Example in Engpsh:
"Watch your step on the stairs, they can be spppery when wet."
"Please be careful and watch your step on the stairs, it's a long way down."
Example in Chinese:
"小心楼梯，湿了很容易滑倒。"
"请注意脚下，小心爬楼梯，下面很深。"