There are three periods in The First Frost, one is "The jackal is a sacrificial animal", the other is "Everything is yellow", and the third is?

The ancients in China divided the first frost into three stages: the first stage was the sacrifice of animals by jackals; Second, the vegetation is yellow; Three stings are salty. At this time, jackals and other animals began to catch prey for the winter; The leaves are all yellow and falling; Hibernating animals also hide in caves and go into hibernation without food.

Extension:

The first frost is the eighteenth of the twenty-four solar terms and the last solar term in autumn. Fight with your fingers; The solar calendar is 210; Celebrate every year on Gregorian calendar 10 year1October 23rd-24th. After entering the first solar term in first frost, the scene of late autumn is obvious, and cold air moves southward more and more frequently.

The first frost does not mean "frost", but refers to the sudden drop in temperature and the large temperature difference between day and night. On the national average, "first frost" is the season with the largest temperature difference between day and night in a year.

Because "frost" is a manifestation of cold weather and large temperature difference between day and night, it is named "first frost" to indicate that "the temperature drops suddenly and the temperature difference between day and night is large". The "first frost" solar term reflects the climatic characteristics of the cold weather, but it does not mean that it will be "frost" when entering this solar term.

In fact, "frost" didn't fall from the sky. The "frost" is the condensation of water vapor on the ground when it meets cold air due to the change of temperature difference. The solar term "first frost" has nothing to do with "first frost".

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