He came up with this Bowden-wedge heel that has to be made out of steel or titanium; if you make it from some sort of cheaper material, it'll actually crack in two.
他想出了这个鲍登楔脚跟 这个必须用钢或钛来做. 如果你用一些便宜的材料制成, 它将会破裂成2半.