求翻译：我不知道你会不会经常上,邮件好像三个月就会无效,如果我过一段时间发封邮件给你,你经常不上,过很久上一次,你也许也能收到我的邮件是什么意思？

I don't know if you regularly, the message seems to be three months would then be invalid if I send you a message for some time, you often can't, the last in a long time, you may also receive the message