Smoking is strictly forbidden on school premises.

校內严禁吸烟.

《简明英汉词典》

Don't leave classroom or school premises while class session without teacher's permission.

上课间,未经老师许可,不可擅自离开教室或学校.

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Must leave school premises within 30 minutes after school ends. Please pick up student on time.

放学半小时后,必须离开学校,不可逗留. 敬请家长准时接走.

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If two semesters, can the teacher remain on school premises during holiday period?

若是两学期, 假期期间外教可否在学校居住?

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The use of tobacco, alcohol or drugs is prohibited on school premises including school parking areas.

禁止在学校(包括校门口和停车场)吸烟, 喝酒和吸毒.

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