Flies, a creature second only to mosquitoes, are repulsive. When the buzzing sound always makes people feel unhygienic!
In the early years, when Ma Weidong was young, he waited for a ferry at the mouth of a certain river, so when he was hungry, he went to the riverside stall to eat flapjacks. (Image from Oriental IC)

Looking at it from a distance, I thought that a layer of drawers had been changed on the flapjack, but it was not clean and slightly dirty. I didn't expect that as soon as people walked up to him, "Hum ~~~~" a bunch of black pressed flies flew up like this! Good guys, there have to be tens of thousands! (Image from Oriental IC)
The boss explained: It's a vegetable fly! Not a feces fly! Eat grain to grow up, not dirty.
At that time, Ma Weidu was disgusted, but there was no way but to pick out a clean stomach in the middle from a stack of cakes. (Image from Oriental IC)