她是个圆脸用英文怎么说

你可以用 "She has a round face" 来表示 "她是个圆脸"。

"Round" 这个词有 "圆的"、"圆满的" 等意思，例如：

The Earth is round. (地球是圆的。)
She has a round smile. (她有一个圆满的微笑。)

"Face" 是指人的脸，例如：

He has a friendly face. (他有一张友好的脸。)
She washed her face before bed. (她睡觉前洗了脸。)

所以 "She has a round face" 就是说 "她有一张圆的脸"。

你也可以用其他形容词来修饰 "face"，例如 "long face" 表示 "长脸"，"square face" 表示 "方脸" 等等。

例句：

She has a long, thin face. (她有一张长而瘦的脸。)
He has a square face with a strong jawpne. (他有一张方脸和结实的下巴。)