1. The most terrifying enemy is the lack of strong belief. ——Romain Rolland 2. Ambition and perseverance are the wings of a career. 3. Only perseverance can make us successful, and the source of perseverance lies in being unwavering and resolutely taking the means needed to achieve success. ——Chernyshevsky 4. As long as you work hard enough, an iron pestle can be ground into a needle.