Dipneusti

例句：

1. 1. The mercury levels in the water are dangerously high.
   水中的汞含量危险地高。
2. 2. Mercury is a toxic substance that can cause serious health problems.
   汞是一种有毒物质，可能导致严重的健康问题。
3. 3. The mercury pollution in our rivers has been a major concern for years.
   我们河流中的汞污染多年来一直是主要关注的问题。