虽然邀请函通常通过信函方式发出，但目前像电子邮件、电话邀请等非正式邀请越来越被普遍使用。

Although invitations are usually sent through the mail, informal invitations such ase-mail and phone invitations are becoming more acceptable.

youdao

虽然邀请函通常通过信函方式发出，但目前像电子邮件、电话邀请等非正式邀请越来越被普遍使用。

Although invitations are usually sent through the mail, informal invitations such ase-mail and phone invitations are becoming more acceptable.

youdao