It's possible that the cleanest and most highly evolved creatures where this topic is concerned are internal parasites, along with bee, wasp and ant larvae.

在这个话题中，最干净、最高度进化的生物可能是体内寄生虫，以及蜜蜂、黄蜂和蚂蚁幼虫。

youdao

He wasn't the cleanest fellow.

他绝不是个爱干净的家伙。

youdao

Britain was the cleanest.

英国是最廉洁的。

youdao

Natural gas is considered the cleanest of the fossil fuels, the fuels created by plant and animal remains over millions of years.

VOA: special.2009.10.23

Use drinking water or the cleanest, clearest water available.

VOA: special.2010.07.19

The group said its aim is to make Manx beaches "the cleanest in Europe".

BBC: Isle of Man pupils join beach clean campaign

Despite the continuing haze, Beijing's air is the cleanest it has been in 10 years.

NPR: Some Economies Suffer As Beijing Cleans Up Air

For years now, Gmail has been widely considered the cleanest and easiest Web-based mail system.

FORBES: Can Microsoft's New Alternative To Hotmail Take On Gmail?