她说法语很好用英语怎么说

"She speaks French fluently" 可以用来形容一个人说法语非常流利。
来源："Fluently" 是形容词，它来自拉丁语 "fluens"，意思是流畅的，顺畅的。
例句：
She speaks French fluently, she must have studied it for a long time.
He speaks Spanish fluently, it's impressive.
翻译：
她说法语非常流利，她肯定学了很长时间。
他说西班牙语非常流利，这很了不起。