Rain gives birth to hundreds of valleys, and spring is full, which makes a solar term.

24. The solar term Song Chunyu is full of spring and clear valley days, (beginning of spring, rain, fright, vernal equinox, Qingming, Grain Rain) summer is full and summer is hot, (long summer, small full, busy middle, summer, little summer, big summer) autumn dew and frost, (beginning of autumn, summer, dew, minute, cold dew and early frost) winter is snowy and winter is cold. (beginning of winter, light snow, heavy snow, winter solstice, slight cold, severe cold)