junk mail

I receive a lot of junk mails everyday. The number of junk mails increased these days. The e-mail address of senders are XXX@yahoo.com or XXX@hotmail.com. The charactor of XXX changes everyday, so it is too difficult to shut out. Though I barred receiving from those senders, as the e-mail address changes everyday, I finally get some junk mails everyday. It's troublesome problem.