He is learning Ancient Greek language.

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.

Old Church Slavonic is the oldest recorded language of the Slavic group.

Old Church Slavonic is the first language written by the Slavs.