1.   And he had bitten his nails so that his fingers hurt and ran with blood.

2.   Biting your nails is a bad habit.

3.   Breaking a habit, be it over-eating, over-drinking, biting your nails or jumping to conclusions, is a tall order.

4.   During a time-out, Eddie bites her nails.

5.   Eddie bit his nails nervously.

6.   Emmie had stood in the doorway, biting her nails.

7.   Her eyes went back to the screen, and she bit her nails.

8.   Her nails were bitten to the quick.

9.   His nails were bitten to the quicks.

10.   I wish I could stop biting my nails.