一种定义
四种语言
0,1,2
- 德國
- 英語
- 中國
- 西班牙語
上行水管 (n)
Steigleitung (f)
riser (n)
In such circumstances, flat treads with risers should be used.
The tread is the horizontal surface that runs from the front edge of a step to the lower edge of the adjoining vertical surface or gap (riser).
