Shit fer brains
One who displays a lack of common sense
A fuckup
A fuckup
Joe really screwed up the assignment. He's such a shit fer brains.
Shit-fer-brains
A southern term for a very dumb individual, is often used to give someone hell if they mess up on something simple.
"Man I tell you, that boy's got shit-fer-brains, he couldn't tell his own ass from a hole in the ground