She's proficient in several languages.

她精通好几种语言。

《牛津词典》

A great number of Egyptians are proficient in foreign languages.

大量埃及人精通外语。

《柯林斯英汉双解大词典》

The children of immigrants tend to be bilingual and proficient in English, "by the third generation, the original language is lost in the majority of immigrant families".

移民的孩子往往会说两种语言，而且精通英语，“到了第三代，大多数移民家庭都丧失了原来的语言。”

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It turns out in the world of classical music there's a stereotype of women being simply less proficient than men: they play smaller than men, they don't have the same force and they have smaller techniques, they're more temperamental and so on.

在古典音乐界,有一个刻板印象,女人的造诣就是不如男人：,她们演奏得不如男人宏大，她们力量不如男人，她们技巧不如男人，她们喜怒无常等等。

耶鲁公开课 - 心理学导论课程节选

Until you're a proficient reader of a language, writing in our language is a fool's errand.

你只有成为一个熟练的读者，才有可能成为一个好的作者。

英语阅读：技巧 - SpeakingMax英语口语达人

Even more staggering, 4% of Detroit public-school 8th graders are proficient in math.

FORBES: Right-To-Work: Does It Improve Teacher Quality?

There was also concern about Iraqi sleeper agents proficient in assassination, kidnapping, and bombing.

CNN: Terror alert level raised to 'orange'

When they joined the revolution, they were already proficient in the use of small- and medium-sized weapons.

BBC: Covert help for Syria's rebels in Jordan