Answer:
What can burn the eyes, sting the mouth, yet be consumed?
I am the heart that does not beat. If cut, I bleed without blood. I can fly, but have no wings. I can float, but have no fins. I can sing, but have no mouth.
I have a neck but no head. I have a body but no arm. I have a bottom but no leg.
I know a word of letters three. Add two, and fewer there will be!
What five-letter word becomes shorter when you add two more letters?
People take me on walks and I run and have fun. What am I?