He was never able to assert himself sufficiently.

他从来不能有效地维护自己的权利。

youdao

He wished to assert himself at work but did not know how to do it.

他希望在工作中显示自己的权威，可是不知道如何去做。

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Can Yao, entering his sixth NBA season, stay healthy and assert himself as an overwhelming presence in the middle?

姚明已经进入NBA第六个赛季，他能保持健康吗，他能确保自己在球场上成为一股绝对不容忽视的存在吗？

youdao

Among the sadder victims of Henry's malignancy is Edsel, who cannot quite assert himself with his father.

WSJ: Book Review: I Invented the Modern Age | Henry Ford

By the time the eighth came around Munroe was well behind on points and although he tried to assert himself on the fight Nishioka's movement was too cute, as he continued to break the spirit of the Leicester man with accurate body shots, while also opening up a cut below his right eye.

BBC: Rendall Munroe loses super-bantamweight world title bid

After being plagued by either injuries (starting after his last major victory at the 2008 US Open at Torrey Pines) or troubles stemming from his marital infidelity (which arose in late 2009) that contributed to no victories in 2010 or 2011, it seems reasonable to assert that Tiger Woods has re-established himself in many ways.

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