Answer:
Kills the bad ones and the sad ones. Tightens to fit, so one size fits.
What grows in winter, dies in summer, and grows roots upward?
Beautiful girls strut and sexy men 'do their little turn' on this.
You can always see it, but it's too far away to touch. Mountains rest on it, and at sea it surrounds you. What is it?
Reaching stiffly for the sky, I bare my fingers when its cold. In warmth I wear an emerald glove and in between I dress in gold.
Almost everyone needs it, asks for it, gives it. But almost nobody takes it.