The day is dry and the night is alert
As a Chinese idiom, the Pinyin is zh ò UG à nx ī t ì, which means to be diligent and cautious day and night. It's from Yi Gan.
Idiom explanation
Be diligent day and night.
The origin of Idioms
"Yi · Gan" says: "a gentleman works all day long. He is vigilant at night, and he has no fault at all."
The day is dry and the night is alert
take advantage of one 's position and power - yǐ guān zhàng shì
submit oneself to sb . 's whims and fancies - fǔ yǎng yóu rén