成绩指数

例句：

1. 1. The student's performance in the exam has a significant impact on his grade index.
   学生在考试中的表现对他的成绩指数有重大影响。
2. 2. The teacher used the grade index to evaluate the students' progress.
   老师使用成绩指数来评估学生的进展。
3. 3. The company's profitability is closely linked to its grade index.
   公司的盈利能力与其成绩指数密切相关。