not know B from a battledore

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 The now-outdated term "battledore" was often used in reference to a children's primer.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.
See also: know, not
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
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