他在沉思过去的苦难。

He broods over past grievances.

youdao

别打扰他，他在沉思。

Don't disturb. He is lost in thought.

youdao

他沉思着，仿佛在思索某个深奥的哲学问题。

He pondered, as if over some deep philosophical point.

《牛津词典》

At a very early age, Milton brooded on his poetic vocation as if it were an actual calling from God.

在很早的时候，弥尔顿就在沉思他的诗歌事业,就像是来自上帝真实的召唤。

耶鲁公开课 - 弥尔顿课程节选