The Coast Guard plays a crucial role in maintaining maritime safety and order.

The border patrol is strictly monitoring to prevent illegal immigration.

He is living as a recluse.

He looked at the bonfire and was immersed in memories.

The Paleolithic is the first era of human history.

The Bronze Age was an important period in human history.

The Neolithic was an important period in human history.

The Mesolithic is the era between the Paleolithic and the Neolithic.

The Azuchi-Momoyama period, also known as the Oda-Nobunaga period, was a very important time in Japanese history.

The Azuchi-Momoyama period was a very important time in Japanese history.