It has its own purpose, which is not a purpose that has any bearing necessarily on anything else.

事物自己存在的目的,与其它无关。

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Now, a virus is not capable of reproducing on its own, so if you got a virus into your body somehow and it didn't enter any of your cells, it would cause no damage because it could not reproduce.

病毒自身并不能繁殖,所以如果你的身体感染了病毒,而病毒没有进入细胞的话,因其不能繁殖所以不会对身体造成伤害

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