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(verbal) abuse; speaking ill of people; bad-mouthing; name-calling; slander; abusive language; insulting remarks
人の悪口を言うのはよくない。
It's not good to speak ill of others.
彼女は悪口を言われて傷ついた。
She was hurt by the slander.
悪口は人間関係を壊してしまう。
Slander destroys relationships.