He’s so dense, light bends around him.

He would be out of his depth in a parking lot puddle.

If brains were taxed, he’d get a rebate.

She sets low personal standards and then consistently fails to achieve them.

If he were any more stupid, he’d have to be watered twice a week.

This employee should go far – and the sooner he starts, the better.

If you give him a penny for his thoughts, you’d get change.

Got into the gene pool while the lifeguard wasn’t watching.