rivie&2&re

例句：

1. 1.The river flows through the city.
   这条河流经城市。
2. 2. The river is a source of fresh water for the town.
   这条河流是这个城镇的淡水来源。
3. 3.We need to protect the river and its ecosystem.
   我们需要保护这条河流及其生态系统。