dorsal flesh

例句：

1. 1. The fish had a dorsal fins that could be seen clearly.
   那条鱼有一根明显的背鳍。
2. 2.The dorsal fin is the most important part of the fish's body.
   背鳍是鱼身体最重要的部分。
3. 3.The dorsal fin helps the fish to swim efficiently.
   背鳍有助于鱼类高效游泳。