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large river
大河を前に言葉を失った。
Standing before the great river, I was left speechless.
大河の流れは悠々として果てしない。
The current of the great river flows on, vast and endless.
アマゾンは世界最大の大河として知られ流域面積も膨大だ。
The Amazon is known as the world's largest river, with a vast drainage basin.