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carrying (someone) on one's back (esp. a child); piggyback ride
relying on (someone); being (financially) dependent on
疲れた子供をおんぶして家まで帰った。
I carried the tired child on my back home.
母におんぶしてもらった記憶が懐かしい。
I miss the memory of getting carried on my mother's back.
小さい頃、祖母によくおんぶされていた。
When I was little, my grandmother often carried me.