unalterable truth
Chinese idiom, Pinyin is B ù y ì zh ī di ǎ n, meaning unchangeable rules. From the ode to the white horse.
The origin of Idioms
Yan Yanzhi's Ode to zhebaima in Song Dynasty: "it's not easy to teach and respect, but it's necessary to teach people."
Idiom usage
To be formal; to be an object; to be derogatory.
unalterable truth
A snake swallows an elephant when the heart is weak - rén xīn bù zú shé tūn xiàng
fit in exactly with one 's wishes - zhèng zhòng jǐ huái
intensive and meticulous farming - jīng gēng xì zuò