Doctor, I haven't been able to get enough sleep lately, and I'm too tired to concentrate in class.

医生，我最近睡眠不足，上课也很困倦，无法集中注意力。

youdao

Second, I usually have to concentrate in class listening to reason.

第二，我平时上课时都专心听讲的的缘故。

youdao

If you concentrate in class and make efficient use of your time, you will get good grades.

如果你上课专注并有效率的利用时间，你就会得到好成绩。

youdao

Beyond economic efficiencies, companies who outsource tend to realize productivity gains as employees concentrate on their core objectives and outsourced resources provide best-in-class support.

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It has been sued in a class action accusing it of forcing "unneeded" beverage concentrate on bottlers to stoke its growth numbers.

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The sheer number of patients allows surgeons to acquire world-class expertise in particular operations, and the generous backup facilities allow them to concentrate on their speciality rather than wasting their time on administration.

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