She fancies herself (as) a serious actress.

她自以为是严肃的演员。

《牛津词典》

In part , her motivation was to prove herself as a serious actress:"I think it's a bit like climbing Mount Everest, "she said.

她有一部分的动机是为了证明自己是个认真的女演员。

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The actress poured herself into serious ballet training to be able to embody the look of a professional dancer and she did a magnificent job of it.

为使自己能体现一个专业舞者的形象，这位女演员把自己投入严酷的芭蕾舞训练中，并且做出了极其动人的表演。

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During a more serious part of the show, actress Emma Stone was brought to tears after she accepted the MTV Trailblazer Award.

CNN: Johnny Depp takes center stage at MTV Movie Awards

The current issue of Forbes shows a more serious photo of the normally seductive and funny Colombian actress Sofia Vergara.

FORBES: Why Sofia Vergara Is the Most Relevant Actress Today