Learn one Chinese Character a day - "口" (学习)
When we were learning the Chinese character "众" or "眾", we have gotten aware of "口", and it is already told that it means mouth.
let us see why it is to mean mouth. image get from http://www.vividict.com/
Does the original Chinese character Oracle script , Bronze script , Seal script all looks like the mouth of human being in the following picture? Chinese ancestors noticed that only human being's face is not covered with hair and it is clearer to see our smile lines than other species.
when it evolved to Official script , it is simplified to what we are using now - "口".
as you can see that "口" original meaning is mouth of human being, it has extended meaning as human being as well. for example "人口" which means population.
and "口" is also eventually used to mean the mouth of all other species.
Since "口" is also the gateway for human beings to eat, "口" is also to mean the place where people, cargo and etc pass through - like "口" of the door( in Chinese is "门" ), we normally say "门口".
as usual, let us enjoy a Chinese Calligraphy -