人们只注重标记可见内容，很容易滥用不可见的内容，或者让不可见内容与可见内容失去同步。

An emphasis was placed on only marking up visible content; it's easy for invisible content to be abused or go out of sync with visible content.

youdao

这七日之久，要吃无酵饼；在你四境之内不可见有酵的饼，也不可见发酵的物。

Eat unleavened bread during those seven days; nothing with yeast in it is to be seen among you, nor shall any yeast be seen anywhere within your borders.

youdao

对于不可见 Flash，这其实没什么影响 — “您需要安装最新版本 Flash” 的 SWF 其实也不可见（当然，也是 1x1 像素）。

For invisible Flash, this does not really matter—the "you need to install the latest version of Flash" SWF is also going to be invisible (well, a 1x1 pixel anyway).

youdao

And these are using the technology to augment the real experiments with virtual atoms that show these things are really there but you can't normally see.

他们在使用这些技术,来积累实际经验,通过模拟原子,使这些东西实际存在,但一般不可见。

麻省理工公开课 - 媒体、教育、市场课程节选

In contrast, on the whole other side, you've got 3 things that are invisible, like the number 3.

相反地，另一方面,有些不可见的东西，例如数字。

耶鲁公开课 - 死亡课程节选

These invisible, vague things can never form the basis of a serious science.

这些不可见，定义模糊的东西,不能被划入严谨的科学范畴里。

耶鲁公开课 - 心理学导论课程节选