He is an expert in ichthyology and has a deep knowledge of marine life.

Cartilaginous fishes do not have bones, instead their bodies are supported by cartilage.

I often go to the sea on weekends.

Umi is my best friend.

The sea breeze feels comfortable.

He found the sea on an old map.

He found the sea on an old map.

I love swimming at the seashore.

He has a wealth of scientific knowledge and is always excited about new discoveries.

He says 'knowledge is power' and studies hard every day.