Rice is one of the world's most abundant food crops. The success of this grain can be attributed to the availability of both manpower for planting and harvesting, as well as plentiful rainfall in the regions where it's grown.

VOA: standard.2010.06.25

So these organisms like this are abundant in the world around us and our immune system prevents us from getting sick most of the time.

在我们周围充斥着像这样的生物体,而免疫系统在大多数时候能够抵御疾病

耶鲁公开课 - 生物医学工程探索课程节选