Some companies automatically delete all email messages more than three months old.一些公司会把三个月以上的电子邮件都自动删除掉。The computer automatically deletes any files you have not saved.电脑自动删除你没有储存过的文件。The system automatically purges unread emails after two weeks.这个系统会于两周后把未读的电子邮件自动删除。