This piece, marked Non troppo allegro, is characterized by its changing meters. The two etudes were composed between 1940 and 1941, during the German occupation. It is characterized by its austere music, reminiscent of Sergei Prokofiev and Béla Bartók. From the outset, within the flow of atonality and changing meters, the left hand repeatedly presents perfect fourth and perfect fifth chords as a motif. One should strive to play the left-hand motif uniformly, ensuring it never falters. At measure 34, the ff chord and the sixteenth-note triplets should be articulated distinctly, utilizing the pedal effectively to prevent the sounds from blending. From measure 68, the opening phrase returns. From measure 86, the left-hand rhythm becomes distinctive. The eighth-note tenutos should be played rhythmically, without becoming too heavy even with pedal, and the sixteenth-note staccatos should not be overly short. The piece builds in intensity towards its climax, concluding with sff. Both hands continue with repeated chords, but one should aim to produce a hard-edged sound where the resonance and clarity of individual notes are not lost.