Vocabulary
爪を噛む癖
つめをかむくせ
habit of biting one's nails
expression
Example sentences
つめをかむ癖（くせ）を止（と）めなければいけない。
You must get rid of the habit of biting your nails.
彼女（かのじょ）は爪（つめ）を噛（か）む癖（くせ）がある。
She has a habit of biting her nails.