My grandfather is seventy years old.

I will explain this matter in detail in the future.

He is majoring in geology at university.

Nazism is a political ideology that was born in Germany in the early 20th century.

It seems that he is suffering from chuunibyou.

He often behaves strangely because of his 'chuunibyou' (middle-school 2nd year syndrome).

He is showing behavior characterized by 'chuunibyou'.

I cannot forget that specific date.

His young and tender heart was very sensitive to new experiences.

His music conveys a sense of youth and tenderness, healing the heart.