We do morning exercises before classes begin.

上课前我们做早操。

youdao

He has to get up before 7:10 and go for a run before classes begin.

他不得不在7：10前起床，然后在课前晨跑。

youdao

[2008-07-23 16:41]--Teenagers need nine hours of sleep a night and parents can help by getting them back on a school sleep schedule before classes begin, researchers suggest.

研究人员日前指出，中学生每天需要九个小时的睡眠，在开学之前，家长们要帮助孩子逐渐回到上学时的作息时间上来。

youdao

One of the things you should begin to do, is to recognize what identifies those classes of algorithms, so you can map your problems into those ranges.

你们现在开始要做的事情之一，就是要学会辨别这些算法,这样你就能为你的问题，选择对应种类的算法了。

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And classes will begin next fall in space loaned by Google to the city while the campus is under construction.

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At Phillipsburg High School in Kansas, 150 iPads were stolen in August one week before classes were to begin.

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Turner is also executive director for student health at the University of Virginia, where classes are slated to begin Tuesday.

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