zhè / tiáo / hé / de / shēng / huà / xū / yǎng / liàng / guò / gāo / shuō / míng / shuǐ / tǐ / shòu / dào / wū / rǎn

这条河的生化需氧量过高，说明水体受到污染。

The river's biochemical oxygen demand is too high, indicating that the water has been polluted.