ascending grade

例句：

1. 1. The students are in the process of moving up to the next grade level.
   学生们正在进入下一个年级水平。
2. 2.The school is implementing a new system that will increase the number of students in the upper grades.
   学校正在实施一个新的系统，这将增加高年级的学生数量。
3. 3.The teacher noticed that some students were struggling with the material and needed to move up to a more challenging grade.
   老师注意到一些学生在材料上遇到了困难，需要提升到更高难度的年级。