be well (/universally)known; be common knowledge; be known to all (/everybody); everybody knows that…/張作霖之死～是日本人謀殺的。(愛新覺羅·溥儀《我的前半生》218) It is common knowledge that Zhang Zuolin was mur dered by the Japanese. ? 至于斷絕八路軍接濟，……等等事實，更是～。(《毛澤東選集》874) It is particularly notorious that promised supplies have been cut off from the Eighth Route Army and…，etc.
盡人皆知
be known to all;be common knowledge
盡人皆知jìn rén jiē zhī
全部的人都知道。be known to all, upon the table, widen known, be a proverb for