Day and night
As a Chinese idiom, the Pinyin is y í R ì B ǔ y è, which means day and night successively. From Huangpu and preface to sixty years of life.
The origin of Idioms
In the preface to Huangpu and its 60th birthday written by Qian Qianyi of Qing Dynasty, it is said that "the song and dance of Qing Dynasty are moving day and night."
Idiom usage
Used as an object or attribute; used in writing
Day and night
make promises easily but seldom keep them - qīng yán guǎ xìn
Drain one's guts and wash one's liver - lì dǎn zhuó gān