细菌是很古怪的东西，它五花八门，几乎无处不有。它们有些繁殖很快，有些却

细菌是很古怪的东西，它五花八门，几乎无处不有。它们有些繁殖很快，有些却难于生长；有些很易被消灭，有些则很顽强；有的寿命很长，有的生命短促；有的带有剧毒，三个五个就可以致人于死，有的却是生物体所大量需要的。

Bacteria are very strange things. They are so diverse that they can be found almost everywhere. Some of them reproduce quickly, but others are difficult to grow; Some are easy to destroy, others are tenacious; Some have a long life span, while others have a short life span; Some are highly toxic. Three or five can kill people, while others are needed by organisms.<br>

Bacteria are very strange things. They are varied and almost everywhere. Some of them reproduce quickly, while others are difficult to grow. Some are easily destroyed, while others are tenacious. Some have a long life, while others are short. Some are highly toxic, and three or five can kill people, while others are much needed by organisms.