She earned her grades through sheer hard work.

她的学习成绩完全是靠刻苦用功得来的。

《牛津词典》

Her grades on the coming exams will fall for sure.

在即将到来的考试里，她的成绩肯定会下降。

youdao

By capping her grades at 94 while most other teachers grade on a scale that tops out at 100, your teacher could jeopardize a student's chance of getting a scholarship or getting into a top college.

如果你的老师把自己的成绩限制在94分，而其他大多数老师的评分范围都在100分以上，那么你的老师可能会危及学生获得奖学金或进入顶尖大学的机会。

youdao

And over a period of time her grades fell completely.

VOA: special.2010.04.22

When his mother learned of his failing grades she required her sons to read two library books every week.

VOA: special.2009.09.04

Perhaps her grades would not go up, but it's better than crashing and being dragged into the river.

BBC: Picture power: Collapsed bridge

Some of the professors were skeptical a woman could succeed in engineering, and the prejudice persisted long after her grades proved real aptitude for the profession.

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Her grades started plummeting.

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