It used to be called a corner. Twelve o'clock was originally created by the ancients according to the natural laws such as the appearance and appearance of the sun, the change of the sky and their daily production activities and living habits. The twelve o'clock clock is unique and has a long history. It is an outstanding contribution of the Chinese nation to the astronomical calendar of mankind and one of China's splendid cultural treasures.
Extended data
Sunrise can be called Dan, Chen and Chen, and sunrise can be called evening, dusk and evening. When the sun is in the middle, it is called noon, noon and pavilion noon, when it is near noon, it is called angle, and when it is west, it is called day. After sunset, it is dusk. After dusk, it's up to people. After a person is appointed, it is midnight (or midnight). After midnight, the chicken crowed. After the cock crow, it is ignorant and dull-this is the time when it is already dawn.
The ancients had two meals a day, and the last meal was before sunrise, which was called eating time or eating early; After sundial, before sunset, it is time to have dinner. This time is called "time".
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