What is the formula for counting nine in cold weather?

The formula for nine days is: 1929, not shooting, and on the ice in 3949. Five, nine, six, nine, see willows along the river, seven, nine rivers open, eight, nine geese. 99 plus 19, plowing cattle everywhere.

There is a folk proverb in China that "the first nine days are warm, and the last nine days are cold". It turns out that if the first nine days are warm, the next winter will be particularly cold. Since March 9, it has entered the coldest stage of freezing.

But in fact, April 9 is the coldest time in winter. It was only a few days before March 9 that the temperature changed greatly, and suddenly it became cold, so the body did not adapt, so it was particularly cold. By April 9, the temperature was lower than that on March 9, but the temperature difference changed little, and it didn't feel as cold as when it entered March 9.

explain

The first sentence: 1929 The winter solstice is already very cold. When your hands are outside, they will be too cold to stand and even get frostbite, so you can't help putting them in your pocket. This is "no hands".

The second sentence: 3949 is the coldest season of the year, and the river is covered with thick solid ice, so pedestrians can walk safely on the river.

The third sentence: The coldest time passed. When the weather began to warm in May 1969, the willow branches planted by the river began to sprout, and everything gradually recovered to remove the winter depression. People could not help but watch the willow trees.

The fourth sentence: In July and September, the ice and snow begin to melt, and the frozen river surface will slowly thaw, and the sound of running water is endless. In August and September, when the weather gets warmer, swallows will fly back from the south to nest and start a new round of busy and endless cycle.

The fifth sentence: 1999 is the "thorn" in the 24 solar terms. I woke up, the weather turned warmer, and there was a spring thunder gradually. The weather is warmer than before. Most parts of China have entered the spring ploughing season, and cattle ploughing is busy everywhere, but it also indicates new hope and a new beginning.