她表示家长们一度担心学习第二语言会削弱孩子讲流利英文的能力。

She says she has known some parents who feared that introducing a second language to their children would hurt the children's ability to speak fluent English.

youdao

优势：年轻精明的教练，可以讲流利的英语，并且在巴萨罗纳队取得了可疑获得的所有荣誉。

FOR: Astute young boss who speaks good English and is winning everything at Barcelona.

youdao

她讲一口流利地道的英语。

She speaks fluent and idiomatic English.

《牛津词典》

He now has super-human mathematical talent, can read and remember the contents of an encyclopedia volume in a few minutes, and speak a language fluently after reading one textbook.

他现在有超过人类的数学能力，能阅读,能在几分钟内记住百科全书的内容,通过阅读一本教科书就可以,流利地讲一门语言了。

哈佛公开课 - 计算机科学课程节选

Can you give us advice about how to speak English well?

如何才能讲一口流利的英语呢？你能给我们一些建议吗？

想学好英语吗？ - SpeakingMax英语口语达人

how many beasts we heard talking good French like that?

我们听过多少“野兽“像那样讲流利的法语？

麻省理工公开课 - 电影哲学课程节选