What did you read in the circled words? What do these four words mean?

Gee, this is the traditional Chinese character "Gu".

Sheung Wan: First half. Dan: In ancient times, sunny days were often used as synonyms for auspicious days.

Gudan, Sheung Wan: The first ten days of a month are sunny and sunny.

Huan: During the Tang Dynasty, officials took a rest and bathed every ten days, which was later called Shang, Zhong and Xia Huan, and the time was three days every month.