curve of order 2

例句：

1. 1. The curve of the riveris breathtakingly beautiful.
   这条河的曲线令人叹为观止。
2. 2. Thecar's curvedroof provides excellent visibility.
   汽车的弯曲车顶提供了极好的视野。
3. 3. The artist used a curve to createa sense of depth in the painting.
   艺术家使用曲线在画作中创造了深度感。