退信的英文：
returned mail

returned是什么意思：
adj. 被送回的；归来的；回国的
v. return的过去式和过去分词；回来

The return of a prodigal
回头浪子

Return ReceiptsSettings for requesting or returning receipts
返回收据有关收据的请求或返回有关的设置

To return disappointedly; defeated.
铩羽而归

The groom returned to the carriage.
马夫回到马车那儿。

Blair will return to London tonight.
今晚布莱尔将返回伦敦。

mail是什么意思：
n. 邮政，邮递；邮件；盔甲
v. 邮寄；给…穿盔甲

Send the memo by express mail.
把这份备忘录用快递寄出。

mail and luggage van
邮政行李车

This parcel came in the mail today.
这个包裹是今天邮来的。

Cn you please confirm that you have received this mail.
您能否确认已收到此邮件

The mail was delivered late today.
今天邮件送得迟了。