and the sandbag shouted its warning

The story:

I sang along to this song all my life. And I admit when I got to this line, I was never quite sure WHAT the heck they were saying so I sang my "sandbag" version anyway. Years later, when the Internet came along, out of curiousity I looked it up. And even though I know what the line is, the "sandbag" line is so ingrained in my brain, that I can never remember the actual line!