Slight summer heat and crouching refer to the beginning of the dog days, but they are not on the same day. Slight summer heat is one of the 24 solar terms, marking the arrival of summer, and crouching is the hottest beginning of summer.

Slight summer is the 1 1 solar term among the 24 solar terms in China. The time of light summer is July 7 or July 8 every year. When the sun reaches 105 degrees, it is light summer.

Slight summer heat is a slight heat, but it is not really hot at this time. Compared with the great summer heat, the ancients thought that it was not the hottest time of the year during the slight summer heat, so this time was a slight summer heat.

In summer, the weather starts to get hot, but it hasn't reached the hottest yet. And crouching marks the beginning of the hottest period of the year, and crouching means entering the dog days. "Summer solstice, three Geng's head falls", which is the basis for establishing the first fall.

The dog days are divided into three volts, which refer to the initial, middle and last volts, from mid-July to mid-August.

The lodging begins on the third Geng day after the summer solstice, with the initial lodging usually being ten days, the middle lodging being ten days or twenty days, and the last lodging being ten days from the first Geng day after beginning of autumn, which is the hottest time of the year.