The purpose of this study is to investigate the adequacy of derivational approach and representational approach to syntactic theories in generative grammar. As the generative grammar is based on the derivational process of syntactic theories, it is suggested that derivational approach is more valid than representational approach. Move, Economy Principle, Local Economy and Label-free Phrase Structure in Minimalist framework support the preference of derivational approach to representational approach with the elimination of computational complexity, minimality, and label-free phrase structure. Syntactic structure is considered as the result of the interaction of the properties of lexical items containing probe and economy conditions constrained by bare output conditions. On the other hand, Pseudogapping in Lasnik(1999) is analyzed in terms of Object Shift, that is, overt raising to Spec of $Agr_o$ and the PF deletion of VP in representational approach. Hence, it is suggested that the combination of derivational and representational approaches to syntactic theories can be admitted in generative grammar.