grade bars

例句：

1. 1. The student's grade bars are clearly visible on the exam paper.
   学生的等级条在试卷上非常明显。
2. 2.The teacher marked her work with grade bars to indicate her strengths and weaknesses.
   老师用等级条来标记她的作品，以显示她的强项和弱项。
3. 3. The students were divided into different grade bars based on their performance.
   学生们根据他们的表现被分成不同的等级条。