该疾病难以察觉地逐渐发展着。

The disease develops gradually and imperceptibly.

《柯林斯英汉双解大词典》

一个彻底的对地方的权利下放也许比渐进地，难以察觉地分权更明智，就像法国在80年代干的那样。

A radical devolution of power to localities, like the one France pulled off in the 1980s, may prove politically wiser than gradual, imperceptible divestment.

youdao

这里隐含着一个难以察觉但非常重要的要求，在设计时，您必须知道目的地是队列还是主题。

A more subtle but important implication is that you had to know whether the destination was a queue or a topic at design time.

youdao

as long as it's small and finite, will lead to some small infinite errors in the formula, but remember it's got to be in the end made to be vanishingly small.

只要它只是有限小,就会在公式中引起无限小的误差,但请记住,Δt最后变得难以察觉地小

耶鲁公开课 - 基础物理课程节选