She frowned with concentration.

她全神贯注，紧锁双眉。

《牛津词典》

In ordinary life, we tend to equate focus with concentration.

在日常生活，我们常把焦点等同于专心。

youdao

Symptoms of BPD can also interfere with concentration, which can lead to poor work performance.

BPD的症状也会影响精力集中，让工作表现变差。

youdao

Lyrica causes side-effects in some patients, including problems with mental concentration and attention.

VOA: special.2011.08.02

It doesn't tell you, this is the equilibrium concentration that you'll end up with.

他无法告诉你,最终平衡时的浓度是多少。

麻省理工公开课 - 热力学与动力学课程节选

And that was when I switched my concentration from computer science to philosophy and psychology with a single question: ? how can I become happier?

于是我将研究方向,从计算机科学转向了哲学及心理系,目标只有一个：,如何变得更快乐？

哈佛公开课 - 幸福课课程节选

Given the Net's collectivist past and regulators' unease with concentration, they haven't abandoned peering altogether.

FORBES: Backbone Bullies

People with the disorder have to deal with problems with concentration, hyperactivity and impulsiveness.

BBC: ADHD Oxfordshire support group criticises NHS

They struggle with concentration issues and poorer health and have lower self-esteem.

CNN: Our unhealthy love of reality TV bullying