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future years; in (one's) later years
後年になってその価値に気付いた。
It was in later years that I realized its value.
若い頃の努力が後年になって実を結んだ。
The efforts of his youth bore fruit in later years.
彼女は後年、社会貢献活動に人生を捧げるようになった。
In her later years, she came to devote her life to social contribution.