Answer:
Deep, deep, do they go. Spreading out as they go. Never needing any air. They are sometimes as fine as hair.
I am not very commonly found! Only in some rainforest! I have an odd number of toes! I'm very lazy and hang upside down! What am I?
What do people spend a lot of money on every year, but never want to use?
I can be in your body but never on your placemat. I'm always better when I'm fresh, but you'll never see me in the flesh. What am I?
I am rarely touched but often held. If you are smart you'll use me well. What am I?
What never gets any wetter no matter how hard it rains?