Struggle against what word?

A good medicine tastes bitter, but it can make up for itself, with a clear conscience, a man can conquer nature, make a great effort, go further, start from scratch, make a comeback, burn one's bridges, throw a pen into the army, open the stone, be diligent and make up for mistakes, have a clear conscience, be ambitious in all directions, be ambitious in thousands of miles, be full of ambition, and make a stab in the arm. Be tireless in learning, be absorbed, be absorbed, be meticulous, be absorbed, read abridged, be tireless, persevere, persevere, read widely, be suddenly enlightened, be tireless in learning, be learned and memorize, be ashamed to ask questions,