Biofilm
生物膜
🗣️ 情景例句
Different kinds of activities, such as commenmorative meetings, planting trees,
举行各种各样的活动，例如召开纪念大会，植树造林，
What on earth has happened to trouble you so?
到底发生什么事让您如此发愁？
He's only forty-one years old, and he has already been to nearly every country in the world.
他只有41岁，但他却过世界上几乎每一个国家。