Answer:
I have joy in bringing two together, but darning my existence! My life hangs by a thread, filled with ups, downs and resistance!
What grows when it eats, but dies when it drinks?
Deep, deep, do they go. Spreading out as they go. Never needing any air. They are sometimes as fine as hair
What can get you there in eco style, pushed by your legs mile after mile?
What is found over your head but under your hat?
I go in hard come out soft. Blow me hard and I’ll make a pop.