uphill and downhill

例句：

1. 1.We need to start our journey uphill before the sun sets.
   我们需要在太阳落山前开始我们的旅程。
2. 2. The hike up the mountain was challenging, but the view from the top was worth it.
   爬山很具挑战性，但山顶的风景值得一看。
3. 3.The car drove downhill at a steady speed.
   汽车以稳定的速度下山。