똥인지 된장인지 분간할 수 없다
shit-be-WHETHER miso-be-WHETHER distinguish-FUTPART able not-have
[He] can’t distinguish whether it’s shit or soybean paste [=miso].
“He can’t tell shit from shinola” or “Wouldn’t know his ass from a hole in the ground” might be similar in tone and meaning.
In the picture at right, the shit is asked: “You… are you shit?” “Are you miso?” The shit answers, “Turns out~ Shit~”