"A curtain of flowers and shadows mops the floor, and the book is in the sky in the middle of the night." I don't know the meaning, origin and background of this sentence. Please ask questions! ~~~

Dai studied in his hometown school since childhood. At the age of 9, he was admitted to Wuyi Education College with his father Dai. 19 years old was admitted to the first place in Ninghe County. In the same year, he went to Sun Family in yutian county to do housework for his widowed aunt and teach two cousins to read. In the eleventh year of Xianfeng, he was born in tribute, took the first grade in the senior high school entrance examination, was a junior official of the household department, and was the alternate principal, leaving Yunnan Division. In the fifth year of Guangxu (1879), Shuntian Township was awarded the title of juren, and in the sixth year of Guangxu, 256 scholars were selected, and palace examination was awarded the second place, and was awarded Jishi Shu, imperial academy. In the eleventh year of Guangxu, he served as the deputy examiner of Jiangnan and awarded a doctor. We have a general understanding of Dai. Dai not only has the talent of writing, but also has unique attainments in calligraphy. This pair of words is great, because Dai's words are well written, and he interprets a story! Because Mr. Dai's calligraphy is very famous, it is known as "southern Dai and northern Dai", and many people want to get the old man's words. One year during the Spring Festival, the couplet written by the old man had just been pasted, and the old man posted another couplet, but when he went out the next morning, he found that the door was gone. It turned out that someone uncovered the couplet at night, which was too strong to be removed. Whoever uncovered it was afraid that it would break. We interviewed Grandpa Dai Zenghan about this matter. Grandpa Dai Zenghan said, I haven't heard of it, but during the Chinese New Year, Teacher Dai came home and criticized the children when he saw that people didn't have couplets and words. "Few people in the village can read, don't you know? After the Spring Festival, if you don't help them write couplets, they will have to pay someone to write them, wasting the living expenses earned by the villagers through hard work and sweat, you know? The old man not only said it, but also personally took pen and ink to write couplets for those who only had red paper on the door. Not only that, he also established a school in Liuzhuang Village through the efforts of the elderly, and finally let Liu Zhuang people go to school. Listening to the legendary story and looking at such beautiful calligraphy make us admire Dai a little more, but any success can only be achieved through hard work. Did Dai try to write such beautiful words? Mr. Dai studied hard since he was a child, so he has to change the quilt once a year, because he not only studies hard during the day, but also reviews what he learns every day when he sleeps at night. Because he thinks and draws on the quilt with his hands, sometimes the quilt is worn out by his fingers in less than a year. In the interview, Grandpa Dai Zenghan told us: "My great-grandfather studied very hard since he was a child and wrote a couplet to encourage himself. This couplet is' a curtain of flowers and shadows mopping the floor, the sound of books in the middle of the night'. Is to study late, go to bed late, and read when the moon is still in the sky.