This area is rich in subterranean rivers, which serve as a source of groundwater.

The airflow in this room is very good.

Superfluidity is a part of physics, referring to the phenomenon where certain liquids flow without friction.

He became a one-eyed person due to an accident.

Oleum is a very dangerous chemical, and it requires great caution when handling.

The flow of the river is very quiet and comfortable.

He is interested in geometrical shapes.

He is conducting research on historical kana usage.

He often thinks about problems from a humanitarian perspective.

His company is facing the risk of a hostile takeover.