Behead me once, and you behold

A pleasure ground for young and old.

Decapitate again, and you will find

I long ago preserved mankind.

Answer: Spark, park, ark.

I have used all my whole this puzzle to frame,

But if you behead me, then murder you name;

Behead me again, and not dead as supposed,

For I still live and breathe, but am much indisposed.