The poem contrasts youth and age.

这首诗对比了青春与老年。

《牛津词典》

Indeed, this story line, with its Shakespearean overtones of youth and age, vigor and decline, is among the oldest in recorded history.

而实际上，这类年轻与老迈，崛起与衰落的莎士比亚剧情，是历史上最古老的线索之一。

youdao

For example, the Old Man and the Sea is a meditation upon youth and age, even though the protagonist spends little or no time thinking on those terms.

比如，《老人与海》是是关于对年龄的思考，但作品中的主要人物并没有在这个问题上花费什么时间。

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The wealth that surrounded her in youth and age were never her own, but always her father's or husband's.

ECONOMIST: Titled English writers

With dry, crisp visual wit and mercurial psychological insight, Hong probes the dreams and delusions of youth and age, and, in a bravura classroom sequence among the finest scenes in the recent cinema he distills the triangle into its rarefied, explosive essence.

NEWYORKER: Oki's Movie

Most of us spent our youth and middle age looking out for No. 1.

FORBES: Magazine Article