Correct

色厉内荏

/ sè lì nèi rěn / 
Strokes

Definition

lit. show strength while weak inside (idiom); appearing fierce while cowardly at heart/a sheep in wolf's clothing

Example

Definition

fierce of mien but faint of heart; fierce of visage but frail of heart; appear severe, but weak inside; strong looking outside but brittle within

1
Tā
他
sèlìnèirěn
色厉内荏
  
。

His rudeness is just a front for his shyness.

2
Sèlìnèirěn
色厉内荏
de
的
rén
人

an ass in a lion's skin