Morphosyntactic Structure. The word morphosyntactic is the adjective of morphosyntax. Morphosyntax is derived from morphology which is the study of word formation and syntax which is the study of how words are combined into larger unit such as phrase and sentence.Morphosyntax is the combination of morphology and syntax.ased on the explanation above, we know that word formation which is the concern of morphology has relationship with the syntactic structure. The word cooks for example is formed from the morpheme cook and the morpheme –s. This discussion occurs in the science called morphology.