谁不知道

who doesn't know?

→ 谁
phrase Rare #23,254
who doesn't know? A rhetorical question meaning that everyone knows something; often used to express that something is obvious or well known, sometimes sarcastically.
CH: 这件事谁不知道?
EN: Who doesn't know about this?

谁不知道

Who doesn’t know?

— 美人鱼 (2016)

这儿谁不知道

Who doesn’t know that around here?

— 利维坦 (2014)

谁不知道

Who doesn't know that?

谁不知道这件事

Who doesn't know about this?

责任感当然谁不知道

A sense of responsibility, of course—who doesn't know that?

— 浪潮 (2008)