Pianists often have trouble in determining where a phrase ends, or in other words, cadence identification. This is especially true of certain cadences that can be considered either as half cadences or authentic cadences. This analytically ambiguous cadential point can result in different performance decisions, so pianists should make informed decisions about what kind of cadence it is. This study aims to investigate such cadential ambiguity shown at points of phrase boundaries by focusing on Chopin's Piano Sonata No. 2 in B-flat minor, Op. 35, first movement. I offer both possibilities (a half cadence or an authentic cadence) at the phrase ending, suggesting a performance-related strategy based on each possibility. My objective is not to support only one cadential status, but to bring up the cadential problem from the analytical perspective and to demonstrate how cadence identification affects performance results. The dissertation is divided into two parts: analysis and performance, so it relies on a combined method of analytical terminologies and performance-related musical elements. In the analysis, the terminology of William Caplin is employed. The performance part refers to several method books written by prestigious piano pedagogues. After an introduction in Chapter 1, Chapter 2 reviews some literature on cadences. Chapter 3 specifically analyzes the first movement of Chopin's second sonata by means of Caplin's terminologies. Chapter 4 provides a performance-related method and Chapter 5 deals with a practical performance strategy.