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charge (of something); matter in one's charge; (one's) assignment; (one's) job
今年の受け持ちは三年生のクラスになった。
This year I was assigned to the third-grade class.
受け持ちの患者が退院したと聞いてほっとした。
I was relieved to hear that my assigned patient had been discharged.
各自の受け持ちの範囲を明確にしてから作業を始めた。
We clarified each person's area of responsibility before starting work.