From which solar terms are the number of volts in summer and nine in winter calculated?

On the third watch after the midsummer solstice, it began to rain. As the saying goes, "Small summer heat is closely related to great summer heat, and it will be hot when the temperature rises." This time is called dog days.

/WB/2007 07 22/2007 07/t 2007 07 22 _ 3 19064 . htm

Counting nine is China's traditional way of recording time. Every nine days from winter, the solstice is nine days, and * * * is nine days. Usually, the first three or nine days of counting nine, that is, winter to the first month in the future, is the coldest day of the year, so there is also the saying of "three or nine winters" or "counting nine winters".