He had a third examination and was declared unfit for duty.

他做了第3次检查，被宣布不适合上班。

《柯林斯英汉双解大词典》

He felt himself from disuse to be unfit for parochial duty.

他觉得自己由于长期不工作，已经不适合做教区的职务了。

youdao

On return to my unit I was placed under arrest to be charged with rendering myself unfit for duty i.e. suicide bid.

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Or maybe the solons will decree that Vermont Yankee is old, decrepit and unfit for further duty (even though it's the NRC's job is to regulate safety).

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