Suppose a man has a car accident. He is hurt badly and is unconscious;that is, he can't think, speak, or hear.His family takes him to the hospital.The doctors tell the family that his brain is dead.A machine can make him breathe.
假设某人遭遇了一场车祸，严重受伤、不省人事， 也就是说．他不能想、不能说、不能听。家人把他送去医院。医生告诉他的家人，这个人已经脑死亡，只能依靠机器的辅助才能呼吸。
