Answer:
I move without wings, Between silken string, I leave as you find, My substance behind.
You’ll have me at night and if you remove the first letter I denote the top, such as on a train
Come up and let us go. Go down and here we stay
A seed am I, three letters make my name. Take away two and I still sound the same.
Sharp and long, flag of the world. What is it?
You can always find me in the past. I am created in the present, but the future can not change me. What am I?