Fluoram
二氟化铵
🗣️ 情景例句
this weekend?
这个周末？
One chick keeps a hen busy.
一只小鸡已够母鸡辛忙。
He has pointed out that the tree is a useful source of income as tour-ists have been coming from all parts of the country to see it.
他指出，由于人们从全国各地纷纷前来参观这棵树，