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idiot; moron; fool
stupid; foolish; dull; absurd; ridiculous
trivial; insignificant; disappointing
malfunctioning; defective; losing sensation
incredibly; unusually; exceptionally
fervent enthusiast; nut; person singularly obsessed with something
Mactra chinensis (species of trough shell)
彼をばかにするのはよくない。
It's not right to make fun of him.
ばかなことを考えるのはやめよう。
Let's stop thinking about stupid things.
ばかみたいに走り続けてしまった。
I kept running like an idiot.