Answer:
I plow and plow but never sow.
When young I am sweet in the sun. When middle-aged I make you gay. When old I am valued more than ever.
Where did the baseball keep its lemonade?
Crooked as a rainbow and slick as a plate, ten thousand horses can't pull me straight. What am I?
I come with a train and go with a train and the train doesn't need me but can't go without me.
If itβs information you seek, come and see me. If itβs pairs of letters you need, I have consecutively three. What am I?