know the difference between one's ass and one's elbow
English edit
Verb edit
know the difference between one's ass and one's elbow (third-person singular simple present knows the difference between one's ass and one's elbow, present participle knowing the difference between one's ass and one's elbow, simple past knew the difference between one's ass and one's elbow, past participle known the difference between one's ass and one's elbow)
- Synonym of know one's ass from a hole in the ground