Answer:
Hold these between your knees if you want to set a Cuban beat.
My first is in blood and also in battle. My second is in acorn, oak, and apple. My third and fourth are both the same. In the center of sorrow and twice in refrain. My fifth starts eternity ending here. My last is the first of last, Oh Dear.
Turn us on our backs and open up our stomachs you will be the wisest of men though at start a lummox.
I am what remains when nothing is left.What am I?
What can you put in a barrel to make it lighter?
All about, but cannot be seen, Can be captured, cannot be held, No throat, but can be heard. Who am I?