Some people have two nails on the tip of their left foot or right foot.

The middle school history teacher said that there are two little toenails, and their ancestral home is Hongdong County, Shanxi Province. One of the most turbulent periods in the history of China in the late Yuan Dynasty and early Ming Dynasty. It was the war at that time that killed almost all the people in the three provinces of North China. Just immigrated from Shanxi. Forced to move to other places, they tied their hands together with ropes to prevent them from escaping. If anyone wants to be convenient, let the soldiers untie their hands. Later, they just said "call it quits", knowing that he wanted to be convenient. This is why "relieving oneself" is also called going to the toilet.