She didn't think that he was well enough to carry out such an exacting task.

她认为他身体不是很好，不能执行如此艰巨的任务。

《柯林斯英汉双解大词典》

But the task cannot be performed mechanically except by exacting obedience.

但是任务不能机械地完成，除非强求服从。

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