But lately he never has his assignments done. And he seems unable to focus in class.

但是最近他常常不完成作业，并且上课的时候也是心不在焉的。

youdao

Kids with ADHD aren't necessarily slow on the uptake, rather they're unable to focus on what's going on.

患有adhd的孩童不一定是反应慢，而是无法专注于周围发生的事情上。

youdao

This led to a somewhat dissatisfying practice, which made me want to speed it up because I was unable to focus.

这导致令人不满的结果，于是我想提高速度，因为我不能集中注意力。

youdao

Also, you might arrive exhausted, sweaty and unable to focus for the first 30 minutes or so of any meeting.

WSJ: Yielding With a Purpose

And employees were trapped in mourning, unable to focus and make decisions.

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For months after Katrina's assault many children now under his watch showed signs of post-traumatic stress disorder: scared to leave their parents, angry or tearful, unable to focus.

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