Metadata attachment is a bit easier with electronic formats.
对于电子格式，附加元数据稍微容易点。
2
If you have any requirement please check by downloading or printing the attachment enclosed in the (electronic) mail.
如果你有需要，可以下载或者打印电子邮件里的附件。
3
A certificate is an attachment to an electronic message used to verify the identity of the party and to provide the receiver with the means to encode a reply.