Fluorated
氟酸盐\\n氟化
🗣️ 情景例句
Robots can be used for many tasks which are considered too dangerous for people to do.
机器人能完成许多对人类来说是很危险的任务。
I learned geography last week.
我上星期学地理。
Twenty year!That's long time.
20年！这个时间可不短。