A part of something bigger, separated from the whole To miss the fairway by a mile, or cut with fine control

I am checked every few minutes, as if that will make me change faster.

I hold the start of human breath, And rock between young life and death. With wooden arms and curved feet, I swing to bring a slumber sweet. No singer am I, yet I sway, To put to rest the busy day.

I have four wheels but cannot drive, I hold your food but am not alive. You push my back to make me start, I travel lines but have no heart. You leave me when your shopping's done, I wait in rows for everyone.What am I?

I am made of wood and metal I'm commonly used for hunting, sports and home defense. I have a long muzzle, with a tubular magazine and a sliding wooden bar underneath said muzzle. I make a very loud audible boom when fired. What am I?