It's eager when put inside an ER. Reds and whites are in its repertoire.

Use your singular of this to solve this riddle I made it easy, making it liddle Goes well with butter Or pesto, marinara, or Bolognese if you prefer.

A heavy weight upon your back, Whether responsibility or horse's tack, You're sat in this if you have control, Grab the reins or handlebars and go!

I rush through forests, I slip through town, I sparkle in sunlight, I murmur in brown. I carry leaves and twigs that fall, I’m not a road, but I still crawl.

Most people don’t think about me until a little icon turns red.