They are more likely to press their lips when asked a sensitive question and are more likely to play with their hair or engage in other “grooming” behaviors.

在被问到较为敏感的问题时，他们更容易按住自己的嘴唇，也更容易拨弄自己的头发，或者做一些其他自我修饰性的动作。

youdao

Press your lips together with the corners straight or down.

把嘴唇并在一起，嘴角成一条直线，向下。

youdao

Great apes press their lips together to express excitement, affection, or reconciliation.

大猩猩也会彼此把嘴唇贴在一起，表达激动、情感或和解。

youdao

Press your lips together with the corners straight or down.

把嘴唇并在一起，嘴角成一条直线，向下。

耶鲁公开课 - 心理学导论课程节选

Nor was it ever established precisely why this boy had devoted himself to the goal of being able to press his lips to every square inch of his own body.

NEWYORKER: Backbone