deleting email messages in mail

Please help! while I'm using my macbook or ipad in mail to highlight an email so I can preview it in the pane, I'd like to be able to go through this process without having the highlight jump to the email above as I review and delete messages. Is there away for the highlight to keep scrolling to the emails below without randomly jumping to the mail message above. I have tons of emails to delete daily but I need to review each one before deleting and this would make life a whole lot less frustrating if I could figure this out. thanks