grind one's teeth

例句：

1. 1. She was grindingher teeth in frustration as she waited forthe results.
   她因等待结果而愤怒地咬紧牙关。
2. 2. Thepatient was gritting histeeth and trying to stay calm.
   病人努力保持冷静，咬牙坚持。
3. 3. He grittedhis teeth and continued to workthrough the difficult task.
   他咬紧牙关，继续完成这项困难的任务。