blood loss

例句：

1. 1. He suffered a severe loss of blood during the accident.
   他在事故中严重失血。
2. 2. The doctor advised him to stay in bed and avoid any further blood loss.
   医生建议他卧床休息，避免进一步出血。
3. 3. Blood loss is a common complication after surgery.
   手术后出血是常见的并发症。