translation.en: The real bacteria and viruses are so small we can't see them without a microscope, and you guys might know bacteria and viruses because they both make us sick.
translation.zh: 真正的病毒和细菌太小了， 小到我们只能用显微镜才能看到。 你们可能对细菌和病毒并不陌生， 因为它们会让我们生病。