咬唇 → biting lip

In the English emotion and expression class, the teacher used the expression picture of biting the lip to teach us to recognize the phrase "biting lip" and explain the emotional meaning it conveys.

The children looked at the nervous expressions in the picture and said "She is biting lip when she is nervous about the exam" in English to describe the emotional action.

In foreign language books, "biting lip" is often used to portray the psychological state of a character who is nervous, shy or entangled, and helps to understand the English expression of emotional expression.