biting

例句：

1. 1.The dog is biting at the ball with its teeth.
   狗用牙齿咬着球。
2. 2.She was biting her nails while waiting for the bus.
   她在等公交车的时候咬着指甲。
3. 3. The mosquitoes were biting him all night long.
   蚊子整晚都在咬他。