The enemy will invariably seek opportunities to assert himself.

敌人是一定要寻找机会表现他们自己的。

《新英汉大辞典》

He was never able to assert himself sufficiently.

他从来不能有效地维护自己的权利。

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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。

youdao

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

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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.

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Of course, Congress has the right to assert that the President himself did not have legal authority to release the information for any reason.

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