Fluorid
n. 氟化物
🗣️ 情景例句
Hi, Tom, this is Mary.
嗨，汤姆，我是玛丽。
Industry is fortune's right hand,and frugality her left.
勤勉是幸运的右手，世俭是幸运的左手。
Wait a moment, I'll be with you in an instant.
等一下，我立刻就来。