ain't got a grain of sense
Is very foolish or lacking common sense. Jimmy almost crossed the street without looking up from his cell phone. He ain't got a grain of sense!
ain't got a grain of sense
and ain't got a lick of senseRur. is or are foolish. Mary spends money like there's no tomorrow. She sure ain't got a grain of sense. I wouldn't trust Jim to take care of my kids. He ain't got a lick of sense.