Carbochromen
乙胺香豆素
🗣️ 情景例句
I haven't dated any one else since her mother died.
自从她母亲去世之后 我从没有和别人约会过。
We are happy to be of help.
我们十分乐意帮助。
Why did you move there?
为什么搬到那里去？