Day and night
Morning and night, Chinese idiom, Pinyin is Zhaoqi á nx ī D à ng, which means to be diligent and cautious all day long. From Yi Qian.
The origin of Idioms
Yi · Qian: "a gentleman works hard all day long. He is vigilant at night. He has no fault."
Idiom usage
He was loyal to his position. Chapter 18 of a dream of Red Mansions
Day and night
compete with each other for beauty of looks - zhēng yán dòu yàn
Back to the mountains and back to the sea - huí shān zhuǎn hǎi
If you don't work hard when you are young, you will be sad when you are old - shào zhuàng bù nǔ lì,lǎo dà tú shāng bēi
the disparity of numerical strength is too great - zhòng guǎ shì shū