Q: iOS 8 Mail - can't delete?

Hi, any help would be appreciated - I upgraded to iOS 8 last night and am slowly getting used to the new features (particularly text, which I hate, but what can you do?) However, I'm having an issue with Mail. I keep seeing all the websites say that when you swipe left, you'll see three options - 'More', 'Flag', and 'Trash'. However, mine doesn't have the option to delete - instead it says 'Archive'. Does anyone know why that is? Is there a way to make 'Archive' and 'Delete' both an option?

Thanks in advance