mail.app question

I have folders for certain people's email's that the inbox emails copy
to. (ie, my supervisor's emails copy into her email folder in mail.app.)
Is there a way to delete the inbox email from supervisor without
deleting the one in her private email box in mail.app? I'd like to clean
out that inbox, truly.
TIA
--
Bush said: 'God...instructed me to strike at Saddam, which I did.'
So, like, did God LIE to the Pope about war in Iraq?
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