For a service by mail, the date of acceptance marked on the receipt of the mail is the date of service. 邮寄送达的,以回执上注明的收件日期为送达日期。
A non-delivery receipt that is sent to an e-mail sender when a message cannot be delivered to the intended recipient temporarily or permanently. 暂时或永久性地无法将邮件传递到目标收件人时发送给电子邮件发件人的未送达回执。