I found it a strain having to concentrate for so long.

我觉得这么长时间全神贯注挺累的。

《牛津词典》

It is difficult to make oneself concentrate for long periods.

让自己长时间聚精会神是很困难的。

《牛津词典》

Originally these were conceived as short stories — early producers doubted the ability of audiences to concentrate for more than the length of a reel.

起初，这些都被定为短篇故事——早期的制片人怀疑观众至多能在一部电影的时间内保持专注。

youdao

They'll say, I usually play for more money and it's hard to concentrate or I'm just screwing around.

他们会说，我玩扑克常常是为了赢更多的钱,但是却难以集中注意力,或者我只是随便玩玩罢了。

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"Humans can only concentrate for 45 minutes at a time, " declares Doris Jeanette, a psychologist with the Center for New Psychology in Philadelphia.

CNN: Experts: Goof off at work, read a book, ignore e-mail

Fahad has only been sailing for three years but he has great control and the ability to concentrate for really long periods of time.

CNN: Oman sails into history in first transatlantic yacht race

Compared with their same-age peers, gifted children may have superior memories, a knack for creating original skits or the ability to concentrate intensely for long periods of time--to cite just a few characteristics of the children inventoried in the test.

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