Give me a ham and cheese sandwich on a bulkie roll.

I have a guilty secret.

And so as we travelled along the country I espied a steeplehouse and I asked them what steeplehouse it was, and they said Dunbar, and it struck at my life that I should have a meeting the next day in the steeplehouse yard.

In some contexts the difference makes no odds; it makes no odds whether we say Tom kissed a girl or Tom kissed some girl, for Tom kissed Mary or Kate is the same in effect as Tom kissed Mary or Tom kissed Kate.