He has real polish - but only on his shoes.
If stupidity was gold, you'd be Fort Knox.
Why don't you act like a desert and dry up.
He's like uncultivated woodland. Totally dense.
I feel sorry for your little mind - being all alone in that great big head.
Fred: I was cut out to be a genius. Georg: It's a shame that the pieces weren't assembled correctly.
She could even give a headache to an asprin.
The last time I saw a face like yours I threw a banana to it.
I'd insult you, but you're not bright enough to notice.
If you ever tax your brain, don't charge more than a penny.