Answer:
My voice is tender, my waist is slender and I'm often invited to play. Yet wherever I go, I must take my bow or else I have nothing to say.
An iron horse with a flaxen tail. The faster the horse runs, the shorter his tail becomes.
At night I come without being fetched. By day I am lost without being stolen.
What goes with a car, comes with a car, is no use to a car but a car cannot move without it?
Two horses, swiftest traveling, harnessed in a pair, and grazing ever in places. Distant from them.
Iām grown from darkness but shine with a pale light. Very round I am and always a lady's delight.