know one's ass from a hole in the ground

Verb

idiomatic vulgar

Japanese Meaning

一定以上の知識や技能を持ち、自分の言動や話題について十分理解していること / 自分の能力や状況を的確に把握し、適切な判断や行動ができる状態

To know one's ass from a hole in the ground is the minimum qualification for that job.

その仕事に就くための最低条件は、最低限の知識や技能があることだ。

Sense（1）

"Why are you so sure and they aren't?" the landsman said. . . .

"Because Mr. Ricimer knows his ass from a hole in the ground, sir."

knows one's ass from a hole in the ground

（ present singular third-person ）

knowing one's ass from a hole in the ground

（ participle present ）

knew one's ass from a hole in the ground

（ past ）

known one's ass from a hole in the ground

（ participle past ）