Cryptogenic
a. 起因不明的
🗣️ 情景例句
No ... thank you.
不……谢谢你。
When a dog is drowning,every one offers him drink.
待到狗溺水，众人给水喝。
A man who had broken his right leg was taken to hospital a few weeks before Christmas.
圣诞节前几周，某人摔断了右腿被送进医院。