grade separation

例句：

1. 1. The school has implemented grade separation to improve academic performance.
   学校实施了分级分离，以提高学术成绩。
2. 2. The government is considering a proposal for grade separation in the education system.
   政府正在考虑一项在教育系统中实行分级分离的提案。
3. 3. The teacher noticed that some students were not mixing with their peers during the morning recess, prompting the implementation of grade separation.
   老师注意到一些学生在上午课间休息时没有与其他同学混合，这促使实施了分级分离。