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schoolyard; school playground; school grounds; campus
子供たちが校庭で元気に遊んでいる。
Children are playing energetically in the schoolyard.
校庭で運動会の練習を毎日しています。
They're practicing for the sports day in the schoolyard.
昔は校庭に大きな木があったそうだ。
I heard there used to be a big tree in the schoolyard.