qī / sāi / mán / shì / yī / zhǒng / gǔ / lǎo / de / wú / hé / yú / lèi / shēng / huó / zài / dàn / shuǐ / hé / hǎi / shuǐ / zhōng

七鳃鳗是一种古老的无颌鱼类，生活在淡水和海水中。

The lamprey is an ancient jawless fish that lives in fresh and salt water.