Glinka's The Nightingale and Variations on Abegg are both difficult. Glinka is a famous composer in The Romantic Period. His works are famous for their complex techniques and rich emotions. Nightingale is a piano solo, which is famous for its quick technical requirements and delicate musical expression. It requires the player to perform accurate fingering and finger independence at high speed, and at the same time, he needs to invest more energy in musicality and expressiveness. Variations on Abegg, a piano solo, is famous for adapting the theme of Herman Franz Abegg. This work technically requires the performer to have excellent fingering and finger independence, because it covers a variety of different skills and musical requirements, including fast scales, arpeggios, jumps and so on. The Nightingale and Variations on Abegg are both difficult works. Players need to have high technical level, musical understanding and playing ability.