Couplet couplets: the cold wind blows hard, and snow falls in front of the first frost house. (Twenty-four solar terms couplets)

It was cold in front of the first frost house, and it was snowy in front of Grain Rain's house in bloom.

Twenty-four solar terms are special festivals in the dry calendar, indicating the change of natural rhythm and establishing "December construction". At first, it was based on the movement of stars. The Big Dipper rotates circularly, and bucket handle rotates around the east, south, west and north, which is called one of the "years old" (Figure). Each rotation cycle begins in early spring and ends in severe cold.

The current "twenty-four solar terms" are formulated according to the position of the sun on the return to the ecliptic, that is, the annual movement track of the sun is divided into 24 equal parts, each 15 is 1, and each 1 is a solar term, starting in beginning of spring and ending in severe cold.

Extended data:

Twenty-four solar terms are a knowledge system formed by ancient ancestors following the agricultural season and observing the movement of celestial bodies to understand the changing laws of time (season), climate and phenology in a year. Farming production is closely related to the rhythm of nature. "Twenty-four solar terms" play a guiding role in farming production and are the reflection of ancient farming culture on festivals.

Monsoon climate is the main feature of China climate. In the monsoon climate, it is wet and rainy in summer and dry and rainy in winter.

The high temperature in the monsoon climate is basically the same as that in the rainy period, and the rain and heat are in the same period, which is very beneficial to agricultural production, because crops grow vigorously and rainwater is abundant when water is most needed.