Bifluoride
[机] 氟氢化物
🗣️ 情景例句
What is your cancellation policy?
我怎么退票？
Have you been listening?
你有没有在听啊？
I left a suitcase on the train to London the other day.
几天前我把一只手提箱忘在开往伦敦的火车上了。