Answer:
The little pink nub that helps rectify mistakes.
A person who chews the ends of their fingers
Ch side by side, you are inside.
What starts with the letter T, is filled with T and ends in T?
It covers you, you lose it every day and you'd die without it.
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.