> I found those mails were moved to mail.mis from Inbox, why?
Hard to tell if you do not show your configuration. It sounds like you
have configured Gnus to split incoming email (sort it into folders).
> How to forbid this.
Depends on your configuration.
Best regards,
--
"Angels can fly because they take themselves lightly." Adam Sj�gren
as...@koldfront.dk