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。

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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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