Lactein
[醫] 煉乳, 乳酸菌素
??? 情景例句
What guarantee do I have that it won't break down easily?
有什么保障它不會輕易出故障？
Constant dropping wears away a stone.
滴水穿石。
The two boys are in the river now.
兩個男孩現在在河里。