The eldest son is being groomed to take over when his father dies.

长子正在接受培养，以在父亲过世后接手父业。

《牛津词典》

John will come into a fortune when his father dies.

约翰在父亲死后可以继承一笔遗产。

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When Hamlet's father unexpectedly dies, his uncle Claudius becomes ruler and marries Hamlet's mother.

当哈姆雷特的父亲意外死亡之后，他的叔叔克劳狄成为国王，并娶哈姆雷特的母亲为妻。

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When his father dies, the boy grows up (a moment dramatized brilliantly by Hou in a single jolting cut), and turns into a quietly wild adolescent of the streets.

NEWYORKER: A Time to Live and a Time to Die