Regiones calcanea
[医] 跟区
🧩 词语组成解析
[医] 掣爪片
🗣️ 情景例句
You're working pretty hard these days.
你这阵子工作得很辛苦呀。
Why are you going back?
你为什么回来？
This would solve the problem of ventilation, for if a train entered this tunnel, it would draw in fresh air behind it.
因为如果有列火车开进隧道，它就把新鲜空气随之抽进了隧道。