He is studying the chronology of Japan.

My father will turn 61 years old this year.

This fish, known as a 'year fish', dies before even a year has passed since its birth.

I received a New Year's gift from my grandparents on New Year's Day.

The time it takes for the Earth to orbit the Sun is called a sidereal year.

Uton is my best friend.

Toshiyuki is my best friend.

I plan to take my annual leave next week.

He was working abroad for a year.

He was working abroad for one year.