You'll have to pay excess postal charges on this letter.

这信你必须付超重资。

All letters must be stamped with the correct postage.

任何信件都应该按所需资贴票。

An aerogramme is writing paper, envelope, and postage all-in-one.You can get aerogrammes at any post office.

航空信就是信纸、信资全一的信件，你任何一个局买到航空信。

Price $14.90, postage included.

价格14.90美元，资包括内。