1, Xiaoshu is not the first day of lodging, as the saying goes, "Three Geng lodging in the summer solstice", which means that it begins to lodge on the third Geng day after the summer solstice.

2. Entering the volt means entering the dog days. "Summer solstice, three Geng's head falls", which is the basis for establishing the first fall. "Three volts" refers to the initial, middle and final volts, which are about from mid-July to mid-August. The first (10 day), the middle (10 or 20 days) and the last (10 day after beginning of autumn) are the hottest days of the year.

3. Chufu is a statement about the calendar method. It refers to the third Geng day after the summer solstice, which is the first day of the three-volt, and usually refers to a period of time from the third Geng day after the summer solstice to the day before the fourth Geng day. According to China's calendar method, it is the beginning of a real summer day. The initial lodging is fixed at 10 day, and the initial lodging begins on the third Geng day after the summer solstice (called lodging).