这个课程采用不分级的教学方式，适合不同水平的学生。

This course uses an ___ungraded approach, suitable for students of various levels.

老师告诉我们这次随堂测验不会打分，只是为了练习。

The teacher told us this pop quiz would be ___ungraded, just for practice.

这条平坦的小路非常适合小孩子学骑自行车。

The ___ungraded path is perfect for kids learning to ride bikes.