What is the quote demonstrating contrast in this paragraph
Little by little, I got better at cleaning her house-good enough to be given more to do, much more. I was ordered to carry bookcases upstairs and, once, to move piano from one side of a room to the other. I fell carrying the bookcases. And after pushing the piano my arms and legs hurt badly. I wanted to refuse, or at least to complain, but i was afraid she would fire me, and I would lose the freedom the dollar she gave me.