All the time you are in doubt about the cause of your illness, you are fighting against an invisible enemy.

一直以来你都在怀疑自己的病因，你是在和一个无形的敌人斗争。

《柯林斯英汉双解大词典》

Such changes are all but invisible over the short time scale of modern observations, and, it is argued, they are usually obscured by innumerable gaps in the imperfect fossil record.

这些变化在现代观测短时间范围内几乎是看不见的，而且，有人认为，这些变化常常被不完善的化石记录中的无数空白所掩盖。

youdao

Imagine how frustrating this game would be if, just as you began to play it, an invisible sniper shot you dead every time.

想象一下，如果在你刚开始玩这个游戏的时候，一个看不见的狙击手每次都把你打死，你会多么沮丧。

youdao

Much of the complexity that we struggle with stems from these seemingly innocuous, innocent and well-intentioned requests which mushroom into invisible processes that take time and effort while adding only minimal value.

FORBES: Are you a complexity creator?

It has auspicious power because it can make itself invisible or visible at any time.

FORBES: Chinese Dragon Still Snorting Loudly

In my household, like so many others across Indonesia, the memories of that time were an invisible presence.

WHITEHOUSE: Indonesia��s Example to the World