know (one's) beans

To be knowledgable about and/or very familiar with something. I had no idea you were such a good piano player—you really know your beans!

Name	Pronounced	Usage
TÓDor	-	Hungarian
EstÈVe	-	Occitan
Hebel	-	Hebrew
Clifford	KLIF-ərd	English
Raimunde	-	German
Paulus	-	Ancient Roman, Biblical Latin