postbox

I dropped my letter into the postbox on the corner before heading to work.

我在上班前把信投进了拐角处的邮筒里。

There is a postbox outside the library, so you can mail the card on your way.

图书馆外面有一个邮筒，你可以在路上把明信片寄出去。

She walked to the postbox at the end of the street to send her application.

她走到街尾的邮筒前寄出了自己的申请。