Cuproscheelite
铜白钨矿
🗣️ 情景例句
Pleasant dreams.
祝你有个好梦。
I've heard so much about you!
久仰大名！
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。