In 2006, Khan made homemade videos to help his ninth-grade cousin with math.

2006年，可汗自己制作视频，来帮助他九年级的表弟学习数学。

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I wasn't looking forward to entering the ninth grade.

我并不期待进入九年级。

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This dream came true for me one afternoon in the ninth grade.

九年级的一个下午，我实现了这个梦想。

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His ninth-grade English class for boys centers on books that he believes boys find interesting.

VOA: special.2010.12.02

This year, 90 students were accepted for admission to Boston Latin's ninth-grade class (14-15-year-olds).

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Though she was a ninth-grade dropout, in 1961 she enrolled in night classes to become a medical assistant.

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Those with a ninth-grade literacy level or higher were 4 to 5 times as likely to maintain their mental capacity with age.

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