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to ill-treat; to bully; to torment; to pick on; to tease; to be cruel to; to persecute
to be tough on (e.g. one's body); to treat harshly
強い人は弱い者をいじめてはいけない。
Don't bully the weak.
いじめられて泣きました。
I cried from being bullied.
人をいじめるのはよくないことだ。
Bullying is not good.