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national railway
Japan National Railways (1949-1987)
国鉄は民営化されてJRになった。
The national railway was privatized and became JR.
祖父は若い頃に国鉄で働いていた。
My grandfather worked for the national railway when he was young.
国鉄時代の駅舎が今も残っている。
The station building from the national railway era still remains.