The ruins from the Kofun Period are important for a deep understanding of Japanese history.

The Ashikaga era is a part of Japanese history.

The Asuka Period is a part of Japanese history, a time when culture and arts greatly developed.

The Muromachi period is a part of Japanese history, a time when many cultural changes occurred.

The Kamakura period was a very important time in Japanese history.

He deeply believes in the principles of socialism.

He is an expert in sociology.

After graduating from university, you have to prepare to enter the real world.

Maintaining social order is the responsibility of all of us.

He understands his responsibilities as a working adult.