rounded cutting edge

例句：

1. 1.The car is rounded and has a smooth surface.
   这辆车是圆的，表面光滑。
2. 2. The tree is rounded at the top and has a thick trunk.
   树顶部是圆的，树干粗壮。
3. 3. The ball was rounded and had a shiny finish.
   球是圆的，表面光滑有光泽。