Spring rains shake the spring and clear the valley, and midsummer is full of summer heat. What does "it's very hot in summer" mean in this poem?

It's a big summer heat and a small summer heat.

Small summer heat: fighting refers to Xin; The solar calendar is 105. Summer heat; Slight summer heat refers to when the climate begins to get hot. Gregorian calendar 06-08 July.

Summer heat: bucket finger c; The solar calendar is 120. The hottest time of the year. July 22-24 of Gregorian calendar.

All the year round begins with "four stands", and the so-called "stand" is the beginning. Beginning of spring, Changxia, beginning of autumn and beginning of winter represent the beginning and arrival of spring, summer, autumn and winter respectively. In order to express the characteristics of time series more accurately, the ancients divided the solar terms into four groups according to the weather and phenology: divided, arrived, opened and closed.

"Fen" means vernal equinox and autumnal equinox, which was called "dichotomy" in ancient times; "Solstice" is the summer solstice and the winter solstice, which was called "the second solstice" in ancient times. "Qi" refers to beginning of spring and Changxia, "Closed" refers to beginning of autumn and beginning of winter, and beginning of spring, Changxia, beginning of autumn and beginning of winter are collectively called "Sili", which add up to * * * to "eight sections". Corresponding to the most important "eight festivals" in the solar terms.

If you choose the key points in the eight sections, it is the "second solstice" of the summer solstice and the winter solstice. In winter solstice, the sun reaches the southernmost point, and in summer solstice, the sun reaches the northernmost point.

In ancient times, from the winter solstice to the summer solstice to the winter solstice (about 365.25 days), that is, the tropic of cancer, it was divided into 24 segments (each segment was about 15: 05), and each segment began with a solar term.

They are: winter solstice, slight cold, severe cold, beginning of spring, rain, sting, vernal equinox, Qingming, Grain Rain, long summer, xiaoman, awn seed, summer solstice, slight summer heat, great summer heat, beginning of autumn, early summer heat, white dew, autumn equinox, cold dew, early frost, beginning of winter, light snow and heavy snow.