Her family adopts a matriarchy.

Oligarchy is a political system where a few powerful people rule the country.

Proportional representation is an important system to ensure the fairness of elections.

My company has introduced a layoff system.

He is doing special exercises to strengthen his depressor muscle.

Primitive communism is one of the initial forms of human social organization.

The system of provinces was a part of the ancient political system in Japan.

The history of the Empire of Japan is very interesting.

The depressor anguli oris is the muscle that lowers the corners of our mouth when we are sad.

She lowered her eyebrows using the depressor supercilii.