Acitinide
锕类
🗣️ 情景例句
we are gathered here today
我们今天聚集在这，
I am sorry Mr. Chen is unavailable, would you like to speak to anyone else?
抱歉陈先生不在，你要不要跟其他人讲话？
The further off this solid obstruction, the longer time will elapse for the return of the echo.
固体障碍物越远。回声返回所用时间就越长。