1、Onychophagia, or nail biting, is a common habit in both children and adults.
咬指甲是儿童和成人常见的习惯。

2、She tried various methods to stop her onychophagia, such as wearing bitter nail polish or using finger fidget toys.
她尝试了各种方法来戒掉咬指甲的习惯，比如涂上苦味指甲油或者使用指尖玩具。