curve of the second class

例句：

1. 1. The curve of the riveris breathtakingly beautiful.
   这条河的曲线令人惊叹。
2. 2. The car's trajectory wasa perfect curve.
   汽车的轨迹是完美的曲线。
3. 3. The path to the summit is markedby steep inclines and sharp turns.
   通往山顶的路标有陡峭的斜坡和急转弯。