noun ダウンロード 🔗共有 水源, 源流 The source of a river, the set of streams that feed into the river's beginning. Examples : "The small stream high in the mountains is one of the Mississippi River's many headwaters. " 山奥の小さな小川は、ミシシッピ川の多くの水源の一つです。 geography environment nature AIとチャット語彙ゲーム読解練習