1. We paddled upriver to reach the hidden waterfall.
我们划船顺流而上，才找到了那个隐秘的瀑布。

2. The villagers live upriver from the city, relying on fishing for their livelihood.
村民们住在城市的上游，以捕鱼为生。

3. The pollution from the factory upriver has been affecting the water quality downstream.
上游工厂的污染一直在影响下游的水质。

4. We will need to travel upriver to get to the remote village.
我们需要沿着河流上游前往偏远的村庄。

5. The boat race will start downriver and end upriver.
这场划船比赛将从下游开始，沿着河流上游结束。

6. The upriver journey was challenging, but the beautiful scenery made it worth it.
沿着河流上游的旅程充满挑战，但美丽的风景让一切都值得。