He was suspended from school for bad conduct.

他因品行不端而被停学。

《新英汉大辞典》

Never had I got a prize at school except once for good conduct.

除了有一次因行为良好得过奖外，我从来没有在学校得过什么奖。

youdao

Father: The school report gives you a D for conduct and an A for courtesy. How did you manage that?

父亲：学校的成绩单上给你的品行分是D，礼貌分是A，你这是怎么搞的？

youdao

Last year, students at the Telfer School of Management (University of Ottawa) and Harvard Business School adopted ethical conduct oaths.

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However, she was suspended from school for "disrespectful conduct" and "public display of affection, " her lawyers wrote in the lawsuit.

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And the Safe Schools Improvement Act, sponsored by Senator Bob Casey of Pennsylvania and Representative Linda Sanchez of California, would require school districts to adopt codes of conduct specifically prohibiting bullying and harassment, including on the basis of race, color, national origin, sex, disability, sexual orientation, gender identity, and religion.

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