亚洲人成影院在线播放高清|久久精品视频免费播放国产|日本亂倫近親相姦在线播放|国产九九免费观看思思

Flies (蒼蠅) usually live in the dirty places.

Let’s look at a fly, and see where it   27 . First, it flies out of the window,   28   it stands on   29  dirty things in the street, and then it flies back to the house and walks over your   30 .?

When a fly walks on the dirty things in the street, its   31   have got some germs  32 them. When the fly walks on your food with its dirty feet, it   33  the germs on your food.

What can you   34  this?

First, we learn that we mustn’t leave dirty things in the street or on the ground near  35 . Second, we learn that all food must be covered so that flies may not   36  it. Third, we learn that flies often carry germs and we must kill them as soon as we see them.