My birthday is on the thirty-first.

My father is forty-one years old.

He is known as a one-hit wonder singer.

Nitrogen monoxide is a cause of air pollution.

He vowed to live through this world and the next with the spirit of once-in-a-lifetime encounter.

Each word and each phrase he said was deeply engraved in my heart.

He is good at one-point reading in shogi.

He was studying all day.

His character is two sides of the same coin, with kindness and strictness coexisting.

The system of 'issei-ichigen' is a historical way of dating in East Asia.