The attackers were said to be taking revenge on the 14-year-old, claiming he was a school bully.

攻击者被称是在报复一名14岁男孩，称他是学校一霸。

《柯林斯英汉双解大词典》

Others lack confidence because of the high school bully factor.

另一些人则因为受过高中校园欺凌而缺乏自信。

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If the bullying happens at school, make sure your parents discuss it with school leaders, not with the parents of the bully.

如果在学校发生霸凌，确保你的父母与学校领导商讨这件事，而不是与霸凌者的父母。

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Johnson described Gadhafi as "the rogue school bully" who, despite the fact that his actions may not be condoned, commands respect for challenging the status quo.

CNN: Gadhafi's legacy in Africa: 'Madman or god?'