not know B from a battledore

To be really stupid, or perhaps illiterate. The now-outdated term "battledore" was often used in reference to a children's primer. It was likely used in this phrase simply for the sake of alliteration. How do you manage to burn pasta? It's like you don't know B from a battledore.

Common Names:

Name	Pronounced	Usage
VÄInÄMÖInen	-	Finnish Mythology
Iael	-	Biblical Greek
Miu	mee-oo	Japanese
Moreland	['mɔ:lənd]
&Thorn;ÓRhildr	-	Ancient Scandinavian
Custodio	-	Spanish