It usually describes someone who is not smart enough and always makes low-level mistakes - as if his head had been cut off with a "kaiser".

Square-brained: inflexible, slow, stupid, dumb. Example sentence: I don't believe it when people laugh at you for being a square-brained person; I don't even know how many one plus one is, but you're a square-brained person.

Ha rub rub ----- stupid hoo hoo. 例句：You ha rub rub, high-voltage electricity can touch ah?

Dumbass, you can't even avoid a train when it's coming, you'll be killed

Square-brained, you can't run away from a train

It means you're too stupid to die

This is the first time I've seen a train in my life.