This study accounts for the correlation between vowel shortening and stress shift triggered by suffixation through foot structures in level-structures. The reason we adopt this approach is that we assume the stress shift and vowel shortening are not separately implemented but they apply simultaneously. Furthermore, this method can give explanations to the phenomena without referring to intermediate derivations and the complexity of rule applications. First, we review a few analytical methods such as phonological rules-based, lexical, CV-level structure, and metrical approaches. Second, due to limitations of these approaches, this study focuses on level-structures to explain the examples discussed in previous studies by suggesting the new devices of a modified Prestress Destressing rule, Minor Weakening and Major Shortening rules, and their conditions for the rule application. Therefore, this study offers more simplified and clearer analytical methods to explain the stress shift and vowel shortening compositely in level-structures than the previous approaches.