She is diligent and keeps herself busy all the time.

她真勤快， 一会儿也不闲着。

《新英汉大辞典》

He is diligent and always keeps his house clean and tidy.

他这个人手勤，屋子收拾得非常干净。

《新英汉大辞典》

Mr. Sunman is diligent.

松曼先生很勤奋。

youdao

And the truth of whether a book should or should not be censored is something that's come about through the diligent effort of a group, rather than a single arbitrary judge like the state licenser.

但一本书是否真正被控制,是一堆人努力的结果，而不是政府出版管理处的人员专横的决定。

耶鲁公开课 - 弥尔顿课程节选

The chorus is a diligent mass of followers until they turn on him, donning chain helmets, chanting "Vanitas!"

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Instead of the constant chase for the shiny new thing, maybe the better bet is more diligent focus on mastering incumbent media.

FORBES: Discipline: The Killer App to Curb Digital Attention Deficit

Romney is the diligent, capable, Mr. Goodwrench-type CEO.

FORBES: Is Mitt Romney Serious? The Presidential Hopeful Must Improve His Demeanor