not know A from a windmill

To be stupid. It references the vaguely similar shape of the letter A and a windmill. How do you manage to burn pasta? It's like you don't know A from a windmill.

Common Names:

Name	Pronounced	Usage
Hertha	['hɜ:θə]
Bettina	[bə'tinə]
Arnold	['a:nəld]
Lawanda	lə-WAHN-də	African American
Benita	[bə'ni:tə]
Asta	AHS-tah (Swedish, Norwegian)	Swedish, Norwegian, Danish