陶然老师的水平，大家都知道，确实挺厉害的。陶然英语网课网盘，一定要好好看的
on the air 广播
We will be on the air in five minutes.我们五分钟以后开始广播。
This programme comes on the air at the same time every day.这个节目每天在同一时间播出
have a good knowledge of sth. “掌握……”，“对……有某种程度的了解”
①He has a good knowledge of London.
他对伦敦有所了解。
②A good knowledge of languages is always useful
on the air 广播
We will be on the air in five minutes.我们五分钟以后开始广播。
This programme comes on the air at the same time every day.这个节目每天在同一时间播出
have a good knowledge of sth. “掌握……”，“对……有某种程度的了解”
①He has a good knowledge of London.
他对伦敦有所了解。
②A good knowledge of languages is always useful
