improper face

例句：

1. 1. She looked at the stranger with an improper face.
   她用一副不合适的表情看着陌生人。
2. 2. The actor's improper face made everyone laugh.
   演员不适当的面容让大家笑了。
3. 3. He tried to hide his embarrassment by giving an improper face.
   他试图掩饰自己的尴尬，露出了不合适的面容。